The Victory Campaign
The Operations in North-West Europe, 1944–1945
Chapter 1: The Development of the Plan for Invading North-West Europe, 1940–1944
(See Sketch 1)
The Beginnings of OVERLORD
The tremendous military enterprise known as Operation OVERLORD—the liberation of North-West Europe from German domination—was launched on the night of 5–6 June 1944. It had been long in preparation. The origins of the undertaking can in fact be traced back to the summer of 1940, when British forces were driven from the Continent after a short and disastrous campaign which ended in the capitulation of Britain’s French allies.*
* See Volume I of this history, Six Years of War, Chapter 9.
This period of planning and preparation is the theme of the present chapter. Volumes could be and indeed have been written on this theme alone. There is no point in recounting the story in all its complexities here. The aim accordingly is merely to provide an outline, not repeating detail already available in reliable studies, but contributing relevant new facts where these have been elicited, and emphasizing aspects of special Canadian interest. The succeeding chapter will deal with the Canadian Army’s own relationship to the development of the OVERLORD project.
From the time of the Dunkirk evacuation the political and military authorities in Britain looked forward to, and planned for, a return to the Continent. An appreciation on future strategy which the British Chiefs of Staff presented to United States officers in the late summer of 1940 said that it was not British policy to try to land on the Continent an army comparable in size with Germany’s; nevertheless, when economic blockade and a mounting air offensive had done their work, a relatively small striking force might be sent across the Channel with good prospects of success. As early as 5 October 1940 the Joint Planning Sub-Committee of the Chiefs of Staff, the principal planning organ, which had lately been brought under Mr. Churchill in his capacity of Minister of Defence, was giving consideration to the problems involved in the establishment of a bridgehead in France.1
Even before this a Commander of Raiding Operations (Lieut.-General A. G. B. Bourne, Royal Marines) and later, from 17 July, a Director of Combined
Operations (Admiral of the Fleet Sir Roger Keyes) had been appointed to study and practise offensive landings.2 But as long as the Commonwealth stood alone against Hitler and his satellites invasion of the Continent remained a highly theoretical notion, and the combined operations planned by the Headquarters instituted for that purpose could be little more than pin-pricks. There seems to have been considerable pessimism in British official circles. In June 1941 the Future Operations Section of the Joint Planning Staff declared that United States belligerency had become essential to victory, but it did not dare to think in terms of large American armies operating in Europe: “The effort involved in shipping modern armies with the ground staff of Air Forces is so great that even with American help we can never hope to build up a very large force on the Continent.”3
The events of 1941 nevertheless altered the picture fundamentally. Russia was brought into the war on 22 June by Hitler’s invasion, and the United States on 7 December by Japan’s attack on Pearl Harbor. Thereafter Germany’s land forces were involved in a debilitating campaign of tremendous scale in Eastern Europe; and the prospect opened of large American forces becoming available for operations against her in the West. Thus the Allied return to the Continent began to present the appearance of an enterprise that might be practicable.
In March 1941, long before the United States entered the war, there had been military “conversations” between British and American authorities leading to a “staff agreement” known as ABC-1. The outstanding feature of this agreement, which though never formally ratified formed the basis of subsequent Anglo-American cooperation, was the declared joint determination, in the event of the United States becoming involved in a general war with the European Axis and Japan, to beat Germany first. When the United States entered the war, steps were taken to carry into effect and extend the tentative arrangements already made. This was done at the “Arcadia” Conference, the first of the important conferences held during the war by the British and American political leaders and their principal service advisers, which took place in Washington between 22 December 1941 and 14 January 1942.4 The conference agreed that “only the minimum of force necessary for the safeguarding of vital interests in other theatres should be diverted from operations against Germany”.5 At this time, however, there seemed to be little possibility of launching a large-scale invasion of North-West Europe during 1942. In the meantime, by setting up the Combined Chiefs of Staff, the conference created an effective instrument for determining and implementing Allied strategy.
The British Joint Planning Staff had outlined in December 1941 an operation (ROUNDUP) to employ six armoured and six infantry divisions, with numerous supporting units, in an assault on the French coast between Dieppe and Deauville—but this assault was envisaged only for “the final phase”, after a serious deterioration in German military power. Mr. Churchill was convinced that, in 1942, the “main offensive effort” in the war against Germany should be the occupation of the North African coastline throughout the Mediterranean.6 This strategic conception was destined to win the day, but only after many months of sharp international discussion.
Allied Uncertainty, January–July 1942
The half-year following ARCADIA was a period of travail for the Allied planners. Germany was to be defeated first; but where was the blow to be struck against her? At the beginning of 1942 American military strength was still potential rather than actual. The planners could not overlook the Allies’ deficiencies in trained divisions and in shipping. If the problem had been simply one of gradual build-up, training and industrial expansion the solution would have been relatively simple. Unfortunately, time was of the essence; early in 1942 the British and American authorities became increasingly worried about the prospects of continued Russian resistance in the vast struggle being waged in the East.
Apart from the Russian factor the planning of an invasion of Western Europe was complicated by fundamental differences in British and American strategic thinking. Influenced by their grievous loss of manpower in the First World War, and the humiliating campaign on the Continent in 1940, the British authorities were reluctant to order an assault which might be premature and which might lead to disaster. Their caution was founded on bitter experience. They preferred an indirect strategy, exploiting superior naval power to attack the enemy at widely separated points on his extended perimeter, thus compelling him to disperse his resources and eventually to present an opportunity for a decisive offensive. On the other hand, the Americans showed great confidence and great impatience for results. They probably did not, as yet, fully appreciate the magnitude of the shipping problem and they would seem to have underestimated the tactical difficulties of an assault on Western Europe. They favoured a strategy of frontal attack-employing the maximum strength against the enemy over the shortest possible distance, and accepting the probability of severe losses in order to obtain decisive success.
The course of Allied discussions on grand strategy during the spring of 1942 has been described in some detail in an earlier volume.* It will be recalled that, at the beginning of April, General George C. Marshall, Chief of Staff of the United States Army, presented to the President a memorandum which recommended Western Europe as the scene of the “first great offensive” against Germany. Apart from immediate raids, two operations were considered: an assault in force which could not be delivered until the spring of 1943, and a limited operation in 1942 to be attempted only if the Russian situation became desperate or German strength in Western Europe seriously declined. The President at once dispatched General Marshall and Mr. Harry Hopkins to London to discuss this plan with the British authorities. The British Chiefs of Staff had been considering the possibility of emergency operations in the West in 1942, but had found no really satisfactory solution to the problem. In these circumstances the London discussions in April produced no final commitment on SLEDGEHAMMER, the limited operation that year; but there was agreement on a major assault (to which the Joint Planners’ name ROUNDUP was applied) for 1943, and on a programme of raids for 1942.
* Six Years of War, 310-23.
During the next few weeks there was pressure both from Moscow and Washington for accelerated action. Another meeting in Washington between Roosevelt and Churchill in June did not result in a definite decision; and when on 8 July the British Prime Minister finally stated frankly the dislike of the scheme for an emergency landing in 1942 which the British strategists had entertained from the beginning, there was some consternation in high staff circles in the United States. The President, who had always been interested in the possibility of action in North Africa, resisted the desire of his senior service advisers to turn away from Europe towards the Pacific. He now sent Mr. Hopkins, General Marshall and Admiral Ernest J. King to London for a decisive discussion. They were instructed to fight for SLEDGEHAMMER, but if unable to convince the British they were to “determine upon another place for US Troops to fight in 1942”.7 The British remained adamant on the SLEDGEHAMMER issue (the War Cabinet discussed the matter on 22 July and “were unanimously against it”),8 and it soon became apparent that “another place” could only be North-West Africa. By. the end of July this orientation of strategy was firm and planning began for the landings in French North Africa which took place in November.
This decision influenced Allied strategy throughout the remainder of the war. Its basic significance is easily stated: the acceptance of the Mediterranean commitment ultimately postponed the launching of the cross-Channel attack until 1944—not, as some people originally hoped, merely until 1943.
The Tactics of Assault
While the North African decision was being hammered out and implemented, and while the political and military chiefs were struggling with the strategic problems of the later phases, an assault technique suitable to the problem of landing troops on the fortified coast of North-West Europe was also being evolved. The evolution was powerfully influenced by a succession of operations which took place while it was in progress. Speaking broadly, it may be said that this tactical planning was in the main a British contribution, and that the largest share in it was that of Combined Operations Headquarters.* This headquarters was directed by Lord Louis Mountbatten, who succeeded Sir Roger Keyes in October 1941.
The British had been accumulating experience in the business of conducting opposed landings since 1940. The minor raids conducted by Combined Operations Headquarters on an ascending scale of size culminated in the considerable enterprise against St. Nazaire on 28 March 1942. The COHQ staff immediately began planning a larger operation, the raid on Dieppe, which was found to fit into the programme agreed with the Americans in April, in which large-scale raids in 1942 were a significant element. The operation was carried out on
* In the United States, the force most concerned with amphibious techniques was the US Marine Corps. No Marine divisions served in Europe during the Second World War, and USMC planners concentrated their attention upon Pacific problems. See Jeter A. Isely and Philip A. Crowl, The US Marines and Amphibious War: Its Theory, and its Practice in the Pacific (Princeton, 1951). The interplay of amphibious experience between the two great theatres has not been much studied to date.
19 August, the 2nd Canadian Division playing the leading part. Dieppe was the only such raid actually executed, and the only major landing attempted against the Germans in North-West Europe before 6 June 1944. It had a powerful influence upon British and Allied tactical conceptions concerning the invasion operation a larger influence than any other single assault.
The Dieppe lessons have already been analysed in the first volume of this history.* That upon which the Army laid most stress was “the need for overwhelming fire support, including close support, during the initial stages of the attack”. This clearly involved a heavy scale of air attack, which—although the Dieppe report was non-committal on this point—would presumably involve participation by heavy bombers, such as had been proposed before Dieppe but eliminated from the plan. It would also involve a naval bombardment much heavier than anything attempted at Dieppe. For close support, “special vessels or craft working close inshore” were required, and since they did not exist they had to be developed. Means had also to be found for using “the fire power of the assaulting troops while still sea-borne”. The Navy considered that the most vital lessons of Dieppe were the necessity for the formation of permanent naval assault forces “with a coherence comparable to that of any other first line fighting formations”, and the importance of training army formations intended for amphibious assaults in close cooperation with such forces.9
November 1942 brought the landings in French North Africa, conducted in the face of opposition which varied between areas but was nowhere on the scale to be expected from the Germans in France. This very large operation nevertheless taught the British amphibious planners various important technical lessons, including the vital importance of special headquarters ships with extra communication facilities (a need already observed at Dakar in 1940)10 In June 1943 came the capture of Pantelleria, a bloodless affair whose fortunate result was due in great part at least to a tremendous scale of preliminary air bombardment. It was followed on 10 July by the assault on Sicily.† This undertaking profited heavily by the experience of earlier operations. The heavy scale of naval gunfire support provided was considered to have yielded excellent results (the bombarding force included three 15-inch monitors and several cruisers). As the result of action taken following Dieppe to improvise special support craft for inshore work, a number of Landing Craft Gun (Large) were present; these (tank landing craft converted to carry two 4.7-inch guns each) had little to do because of the light resistance encountered, but were favourably reported on.‡ Another result of Dieppe was the presence of Landing Craft Tank (Rocket)—LCTs converted to mount 800 (later 1100) 5-inch rocket projectors to “drench” beach defences just before the assault. Also making its first appearance was the Landing Craft Assault (Hedgerow), an LCA able to project a salvo of 24 60-pound bombs a short
* Six Years of War, Chap. XII.
† See Volume II of this history, Lt.-Col. G. W. L. Nicholson, The Canadians in Italy, 1943–1945, Chap. III.
‡ The Landing Craft Gun (Medium), to carry 17-pounder guns, was specially built and none was available for the Normandy landings. The Landing Craft Support available at the time of Dieppe carried nothing heavier than a 6-pounder.
distance; its function was to produce, at the moment of the assault, a gap through enemy minefields and wire obstacles through which our troops and vehicles could advance.11
Special craft and vehicles, most of them built in the United States, were now appearing in large numbers. Sicily saw the first really large-scale use in the war against Germany of the Landing Ship Tank, capable of landing large numbers of tanks or other heavy vehicles directly on to beaches if the gradient of the latter was suitable. The LST was henceforth to be a staple support of amphibious operations. The diesel-powered Landing Craft Infantry (Large), able to carry about 200 soldiers, also proved itself, though it was too bulky to use in the first wave of an assault. Finally, the first amphibious vehicle, the American DUKW, a 2½-ton amphibian truck, made its bow in European waters in this operation and, in Admiral Ramsay’s words, “fulfilled our highest expectations”.12
There were valuable administrative lessons. The new equipment, plus the army organization known as the “Beach Brick” (later “Beach Group”), set up to assist in unloading and loading, had made it possible to maintain a large military force by stores landed over open beaches. This opened up the prospect of being able to mount a major invasion without the condition, heretofore considered indispensable, of capturing a large port in the first stage. In the light of the Dieppe experience, which indicated how difficult such a capture was likely to be, combined with the fact that the Germans were concentrating their defences in North-West Europe chiefly around the ports, this was extremely important. But the Mediterranean is an almost tideless sea, and this lesson could not be applied to operations in the English Channel without many reservations.13
The large-scale landing at Salerno early in September 1943 produced experience which reinforced that of earlier operations. Owing apparently to the army planners’ desire to ensure surprise, there was no naval or heavy air bombardment before the assault. (This was in contrast with the bombardment that preceded the virtually unopposed landing on the toe of Italy a few days earlier, in which the 1st Canadian Division took part.) But in the subsequent fierce fighting on shore the troops were effectively supported by heavy naval ships as well as by both the Strategic and Tactical Air Forces. Some accounts indeed credit the saving of the situation to intervention by battleships; but an Admiralty analysis concludes that the worst of the crisis was over before the Valiant and Warspite came into action. Vice-Admiral H. Kent Hewitt, the American officer who was in command afloat, reported after the action that heavy preliminary air and naval bombardment was essential before a landing on defended beaches. Combined Operations Headquarters considered that, apart from this, the chief lesson of Salerno was the limitation of the duration of effective air cover that could be provided from aircraft carriers. Fortunately, land-based air support had also been available.14
While the experience here so briefly summarized was being bought with blood, experts in England were engaged in analysis and experimentation designed to produce a “tactical doctrine” suitable to the assault on North-West Europe.
The recommendation after Dieppe that permanent naval assault forces be formed resulted in the Dieppe naval force itself being kept in existence. As Force J (JUBILEE), constituted under this name on 12 October 1942 and commanded in the first instance by Commodore John Hughes-Hallett, the Dieppe Naval Force Commander, it worked in the Channel as a practical experimental laboratory and training unit for Combined Operations Headquarters. It carried out no actual operation between Dieppe and the Normandy D Day, though most of its ships and craft were used in the Sicily operation; but its activities made a material contribution to the tactical plan for the Normandy landings.15
By the summer of 1943 that great operation was beginning to take shape. The COSSAC staff (see below) was preparing a strategic plan, and it was evident that the Allies’ ideas on tactics, equipment and training for the assault required to be reduced to definite form. After discussion with COSSAC, therefore, Lord Louis Mountbatten arranged for a conference (known as RATTLE) to be held at the Combined Training Centre at Largs on 28 June-1 July. Among those attending, in addition to Admiral Mountbatten and Lieut.-General Morgan (COSSAC), were the C-in-C Home Forces (General Paget), the Commander-in-Chief Portsmouth (Admiral Sir Charles Little), the Commanding General European Theatre of Operations, USA (Lieut.-General J. L. Devers), Air Marshal Sir Trafford Leigh-Mallory (C-in-C Fighter Command) and Lieut.-General A. G. L. McNaughton, GOC-in-C. First Canadian Army; as well as senior officers from the various formations and establishments, of all three services, which would be concerned with the plan.16
The conference considered navy, army and air aspects of the projected operation and reviewed the existing state of equipment and the needs of and facilities for training. Of all the problems which received attention, the one most anxiously canvassed was that of support for the assault; and the particular part of it about which most apprehension was expressed was fire support during the period between the lifting of the naval and air bombardment a little before the troops actually reached land, and the time when the army got its own guns into action ashore. Lieut.-General G. C. Bucknall, then commanding the 1st British Corps,* had been directed by GHQ Home Forces on 29 May to train and equip his corps “to carry out seaborne assaults on the north east coast of France” and to study—and report on the technique of the assault.17 During RATTLE Bucknall produced a tentative answer to this support problem which had much in common with the solution that General Crerar of the 1st Canadian Corps was evolving at this same period (see below, page 35). Bucknall did not, like Crerar, propose organizing the support craft in four successive flights according to the range of their weapons, or to attempt to pass the shorter-range flights through the longer-range ones as they approached the beach; but he did propose successive offshore echelons of fire support in each brigade sector, with Hedgerows, LCGs., flak landing craft and small support craft, and LCTs. (Rocket) all playing their parts, and with two regiments of self-propelled field artillery firing from LCTs.
* Subsequently he was transferred to the 30th Corps, and Lieut.-General J. T. Crocker took over the 1st for the assault.
This was in addition to monitors and destroyers as might be allotted. Bucknall proposed that the initial landings should be made “just before first light”. Commodore Hughes- Hallett welcomed these proposals but pointed out that they had revolutionary implications for the naval plan. They involved composite forces of craft of different sizes and speeds which would have to form up off the enemy coast in the dark. This was “almost an impossible problem” from the naval viewpoint. The composite forces could be formed up and could make the assault as suggested, provided the naval and military assault forces trained together; but the forming up would have to be done in daylight. In other words, a daylight assault was clearly indicated.18 On the final day of the conference this view was endorsed by Sir Charles Little.19
At this final session, General Paget made an address20 which dwelt upon the dangers and difficulties of the proposed assault, “an operation the like of which had never been undertaken in the history of war”. He said that no solution had yet been found for the problem of fire support in the last stages of the landing (at this moment, before Sicily, the new support craft had not been tested either in action or in a large combined exercise), but forthcoming tactical trials would carry the matter “a stage further”.
The 1st British Corps was already working hard at experimentation, though it had not carried out any large-scale assault exercises. A series of planning exercises had given valuable experience to various headquarters. A Corps study period held on 23-26 June, immediately before RATTLE, had crystallized and summarized ideas and experience and given Bucknall a basis for his RATTLE exposition.21 Various special tactical aspects had been investigated. Exercise KRUSCHEN, conducted by the 163rd Infantry Brigade in April, had thrown light upon the means of “driving the Germans out of their concrete defences in the Coastal Areas of NW Europe”, experimental assaults being conducted against a full-scale model of a German “hedgehog”. This was not an amphibious exercise.22 At the same period (March-April 1943) Exercise PRIMROSE at Kilbride Bay witnessed what seem to have been the first actual experiments in the employment of self-propelled army artillery firing from tank landing craft in the assault.23 By the late summer the 1st British Corps was conducting exercises at Kilbride with air and naval cooperation. In EUCLID, carried out by the 49th Division in August and September, no troops seem to have been actually landed; but in NIMBUS in the latter month an infantry battalion and a field battery were landed covered by attacks by light and fighter bombers.24 On 6 September the Corps Commander held a discussion which foreshadowed many of the actual techniques to be used on the Normandy D Day; notably, the arrangement by which the DD (amphibious) tanks formed the first wave of the assault, followed some minutes later by the AVREs (Assault Vehicles, Royal Engineers),* with the leading infantry a short distance behind them. It assumed that fire support before the landing would be afforded by self-propelled artillery, by rocket craft, and by the heaviest possible scale of naval bombardment. Air support was not discussed to any extent.25
* Six Years of War, 403-4. The intervals between the tanks, the AVREs and the infantry in the final plan were not precisely those recommended at this time.
While the tactics of the assault were thus being evolved, administrative support for the invasion operation was receiving equal attention. Two major exercises deserve mention in this connection. One was JANTZEN, whose object was “to practise the maintenance of a corps and supporting troops through the beaches for 14 days”. It began in April and May 1943 with planning by Headquarters 1st British Corps and 61st Division on the basis of a two-brigade assault. In July (the 22nd being D Day) the 1st Corps actually carried out the administrative landings, under the direction of Headquarters Western Command, on beaches near Tenby, South Wales. Only administrative troops took part, but approximately 16,000 tons of stores were physically landed during the exercise.26 Even larger in scope was Exercise HARLEQUIN, conducted during August and September. Its object was “to try out the procedure and machinery for passing troops from Concentration Areas through Assembly and Transit Areas to embarkation hards and ports”; the exercise represented an embarkation programme for the invasion of the Continent extending from D Day through D plus 3. Two Corps were involved, one (the 12th British Corps) passing through assembly areas in the Dover and Newhaven sectors, the other (the 1st Canadian Corps, with the 2nd Canadian Division and 5th Canadian Armoured Division under command) through areas in the Portsmouth and Southampton sectors.27 On reaching the waterside, most of the force simply turned away and dispersed. A certain number of anti-aircraft units, none of them Canadian, were embarked and went for a Channel cruise; for this exercise was being combined with a deception scheme (STARKEY) intended to convince the Germans that an invasion was intended, and to bring on a large-scale air battle28 (see below, page 15). The 21st Army Group reported a trifle sourly that the fact that HARLEQUIN formed part of an operation “directed by another Service with a different object” resulted in lack of realism; nevertheless, the enormously complicated machinery for moving an invasion force to the ports and embarking it in general performed well, and valuable lessons were learned which enabled improvements to be made.29
Special armoured equipment for the assault had long been under development. The Assault Vehicle, Royal Engineers, had come into existence as a result of the Dieppe experience. The amphibious or DD tank (below, page 00) was to see action for the first time on the Normandy beaches. The Flail tank for exploding minefields had been used, in an early form, in North Africa. The “Crocodile” flame-thrower (which was, like the AVRE, an adapted Churchill tank) had been favourably reported on in Exercise KRUSCHEN. This special armour was the responsibility of Major-General P. C. S. Hobart, commanding the 79th Armoured Division, who in April and May 1943 received directives requiring him to “develop a technique for the specialised units which have been placed under your command and to train them to form part of formations assaulting either beach defences or inland defended areas in Western Europe”. He was instructed to maintain close contact with the 1st British Corps.30
Testing the Assault Tactics
It fell to the 3rd Canadian Division (see below, pages 34-36) to conduct the first full-scale trial of the assault. technique which was being developed. This was Exercise PIRATE, staged in October 1943 at Studland Bay, Dorset in cooperation with Force J and Nos. 11 and 83 Groups RAF. Its object was “to exercise the forces of all three Services in their functions during a major combined operation”. The plan included practising embarkation, assault against a heavily-defended beach, the work of the “Turn Round Control” organization (Turco), which controlled shipping during the build-up phase, and even the rapid construction of an airfield in the bridgehead. Particularly vital was the fire plan for the assault, which was the subject of a detailed memorandum by General Crerar sent to the GOC 3rd Division on 30 August and included most of the elements that had emerged from the operations and studies of the last few months: naval bombardment (destroyer gunfire, supplemented by rocket fire and Hedgerows during the final approach, and close support craft carrying tanks which beached in the first wave to engage the beach defences); air bombardment (attacks by medium and light bombers before the landings, plus cannon and rocket attacks by fighters); and a “beach barrage” by two field regiments of army artillery firing from tank landing craft.31
D Day for PIRATE was 17 October. Unfortunately, the proceedings were disrupted by “bad weather in the opening stage which necessitated a change of the general plan and which shut down again after the assault and terminated the exercise prematurely”.32 “Fog on inland airfields prevented the smoke-laying and bombing aircraft taking off and with the exception of the provision of air cover to the convoy at sea and dummy attacks by Typhoon aircraft against pre-arranged targets on the beaches, the air support plan as arranged was not carried out.”33 In spite of these and other deficiencies (below, page 00 [sic]), the exercise was judged to have been a success; the conclusion of the 3rd Division’s commander (Major-General R. F. L. Keller) and his staff was that the “Combined Fire Plan of RN, RAF and Army proved itself to be workable and feasible, subject of course to further training based on the detailed lessons learned”, and that it had been shown that army artillery while seaborne could carry out a successful “area shoot”. Hedgerows and AVREs had done their work well.34 It appeared that a firm foundation now existed for an assault plan, and in succeeding exercises Force J and the 3rd Division were able to confirm the soundness of the PIRATE conclusions.*
An incidental result of the exercise was to revive the controversy over whether a daylight H Hour was or was not practicable. Air Marshal J. H. D’Albiac, Air Officer Commanding Tactical Air Force, strongly recommended in his report that the Navy reconsider its objections to a night approach and a dawn assault; he held that an approach in daylight would mean heavy losses from artillery fire and air attack. General Paget disagreed. With respect to the artillery menace, he considered that most of the enemy’s coast-defence guns would have been
* On PIRATE, see also below, page 36.
neutralized or destroyed before the assault. As for the danger of air attack, he took the view that if we had not acquired a sufficient degree of air supremacy to prevent really heavy attacks by the enemy air force, then the assault should not be attempted at all.35 The daylight attack continued to hold the field, and was incorporated in the final plan.
At the time when PIRATE took place the basic problem of fire support was receiving further formal study. In August 1943 the British Chiefs of Staff set up a special inter-service committee to consider it. It was headed by Air Vice-Marshal Ronald Graham of Combined Operations Headquarters; it included senior representatives of all the services and had the advantage of consultation with many experts, military and scientific. Its report36 was complete by December. Only its recommendations can be summarized here. The committee concluded that “in general, our existing means of naval and air support are satisfactory”. It emphasized however the need for action to improve, if possible, the accuracy of naval and air bombardment; it made recommendations for improving the effectiveness of special support craft; it urged the importance of developing means for dealing with coast-defence guns in turrets and casemates by air bombardment and for destroying obstacles, including minefields and underground shelters, that could not be dealt with adequately by existing means available to the Army. It represented the need for improving the performance of naval high-explosive shell[s] against targets ashore and the arrangements for aircraft recognition and control of anti-aircraft fire. It called for further investigation of “the problem of the best time [of day] for an assault against a heavily defended coast”. Finally, it urged that the authorities concerned, including the service ministries, “should be instructed that proposals submitted for improving the degree of fire support in a seaborne assault should receive attention on the highest priority, and, when promising, should be developed in high priority”. This basic recommendation was implemented by the Chiefs of Staff on 23 December 1943.37
Allied Strategic Planning, 1942-43
While assault tactics were being developed in this thorough manner, Allied strategy was moving on towards the invasion of North-West Europe in which these tactics were to be utilized. The story has been told more than once, by some of the major participants and others; here, accordingly, it can be briefly summarized.
Long before the Allied landings in French North Africa in November 1942, the British and American leaders had been discussing the next step. The Americans felt certain from the beginning that the African project meant that there could be no major attack in North-West Europe in 1943; Mr. Churchill, while loath to admit this, was considering exploitation operations in the Mediterranean as well as an enterprise in Norway.38 In January 1943 President Roosevelt and the British Prime Minister met with the Combined Chiefs of Staff in conference at Casablanca. The result, arrived at in the face of strong initial American military opposition, was a decision to exploit in the Mediterranean by
invading Sicily that summer. Along with this, however, went the further decisions to conduct from the United Kingdom “The heaviest possible bomber offensive against the German war effort” as well as “Such limited offensive operations as may be practicable with the amphibious forces available”, while at the same time assembling there the strongest possible force (subject to prior commitments elsewhere) “in constant readiness to re-enter the Continent as soon as German resistance is weakened to the required extent”. The Combined Chiefs recognized that there was now no chance of being able to stage a large-scale invasion of the Continent against unbroken opposition during 1943. They proposed to prepare for the following possibilities: small-scale amphibious operations; re-entrance to the Continent in the event of a sudden collapse of German resistance; operations to seize a bridgehead late in 1943, in other words a form of SLEDGEHAMMER; and, finally, “an invasion in force in 1944”.39
To implement this programme the Combined Chiefs agreed to establish forthwith “a Combined Staff under a British Chief of Staff until such time as a Supreme Commander with an American Deputy Commander is appointed.”40 The result was the appointment in March 1943 of Lieut.-General F. E. Morgan as “Chief of Staff to the Supreme Allied Commander (designate)” (COSSAC). General Morgan set up his headquarters in London and began work under a directive, approved by the Combined Chiefs of Staff on 5 March, which was superseded by an amended directive on 23 April. This latter paper instructed Morgan to prepare plans for three projects. First, he was to plan “an elaborate camouflage and deception scheme” extending over the whole summer of 1943 with the idea of “pinning the enemy in the West” and keeping alive the expectation of large-scale cross-Channel operations that year. There was to be “at least one amphibious feint” intended to bring on a large air battle. Secondly, he was to prepare a scheme for “a return to the Continent in the event of German disintegration” at any time, using such forces as might be available at the time. And thirdly, he was to plan “a full scale assault against the Continent in 1944 as early as possible”.41 It will be noted that the idea of a 1943 SLEDGEHAMMER had been dropped.
On 25 May 1943, as the result of discussions at the TRIDENT conference then in progress in Washington, Morgan was given a supplementary directive. This fixed the “target date” for the full-scale assault at 1 May 1944. It also specified the forces whose presence in the United Kingdom might be taken as a basis for planning: for the assault, five infantry divisions “simultaneously loaded in landing craft”, two infantry divisions “as follow up”, and two airborne divisions; while 20 more divisions would be available for movement into the lodgement area as “buildup”.42 It simultaneously emerged, however, that Morgan could not in fact count on using five seaborne divisions in the assault. There were simply not enough landing craft in prospect. The Combined Chiefs of Staff at this same conference adopted the assumption that the British (including presumably the Canadians) would provide “two assault divisions and one immediate follow-up division” and the United States “one assault division and one immediate follow-up division”.43 The RATTLE conference in June was told, with reference to this assumption, “The two [immediate] Follow-up Divisions would be tactically
organised and loaded in craft, but would not be provided with the right type of craft for an assault”.44 General Morgan, in fact, was limited to an assault by three divisions.
COSSAC organized an “integrated” Anglo-American staff composed of officers of the three fighting services.* A few Canadian Army officers were included, one of them being General Morgan’s Military Assistant, Major R. A. Harris.45 The COSSAC action taken in connection with Morgan’s first two tasks can be briefly described.
The plan for the 1943 deception scheme culminated in Operation STARKEY, of which as we have seen Exercise HARLEQUIN formed a part. Much thought and effort went into STARKEY, not to much apparent effect. The object was to convince the enemy that a major amphibious operation was to be delivered against the Le Touquet area of the Pas de Calais. On D Day, 8 September, an “assault convoy” carrying numerous army antiaircraft units approached this area from the direction of Dungeness. A convoy of some 20 large mechanical transport ships also manoeuvred in the Channel. The German long-range batteries in the Pas de Calais were bombed that morning and the previous night, and there were also air attacks on airfields. Minesweepers were sent out to clear the way for the assault convoy. Considerable air forces covered the naval units and were in readiness to strike at the German Air Force if it chose to offer battle.46
Unfortunately, it did not. “Enemy fighter reaction was, in general, slight.” The German coastal guns did not open fire on the “assault convoy” as it trailed its coat in front of them. The enemy, in fact, in the words of the 21st Army Group’s report, refused “to be hoodwinked into fighting on our terms”.47 Available German documents, while not so specific as could be wished, indicate that the enemy had appreciated that a large-scale invasion exercise was in progress. Although not misled into thinking an attack was imminent on 8 September, he was acutely apprehensive that invasion might be impending. The Commander-in-Chief West’s situation report for the week ending 13 September remarked, “For a serious attack—despite a maximum commitment of 2500 aircraft on one day—the tempo and sequence of the air attacks were not fast enough.† In spite of this a transition to actual invasion is possible at any moment.”48 Though the deception plan which reached its climax in STARKEY failed in its immediate object of bringing on an air battle, it did contribute to keeping the Germans on tenterhooks and may well have prevented the transfer of forces to the Eastern Front.
The plan for invasion in the event of German “disintegration” went by the code-name RANKIN and was complete in outline by the middle of August 1943. It was prepared under three headings: “RANKIN Case A” assumed a mere “thinning out” of the enemy forces in North-West Europe; “Case B” assumed complete enemy withdrawal from certain portions of his coastal line while continuing to
* The staff organization is described in General Morgan’s book Overture to OVERLORD, Chap. II, and in Chap. II of Gordon A. Harrison, Cross-Channel Attack.
† By this time the Germans had had important assistance from our side in making their appreciation. On 9 September a joint Admiralty-War Office-Air Ministry communique announced, “A full-scale amphibious exercise has recently taken place in the English Channel.”49
hold the balance; “Case C” postulated a complete collapse of the Nazi system. This last contingency, it soon appeared, involved many questions relating to the administration of liberated or conquered territories which required attention in connection with the main invasion plan. For this reason “Case C” was developed by COSSAC in more detail than the other portions of the plan. Headquarters First Canadian Army produced a detailed operation instruction covering its part of the plan.50 But as the Nazi system did not disintegrate until the German armies had been defeated in the field, none of the RANKIN plans ever came into operation, and accordingly no more will be said of them here.
The COSSAC Plan for OVERLORD
COSSAC’s main task was the preparation of a plan for invading the Continent in the face of opposition in 1944. In preparing this the COSSAC staff had the advantage of being able to utilize the work of earlier planning groups.
On his arrival in London in March 1943 General Morgan was “made free of this vast bibliography” and particularly of the papers produced by or for the “Combined Commanders”. This group, the British officers of the three services then designated for the senior commands in the invasion operation, with the Commanding General of the US forces in the European theatre associated with them, had been engaged since the spring of 1942 in studying the problem of [a] return to the Continent.* In February 1943 the Combined Commanders’ planning staff had produced a study entitled “The Selection of Assault Areas in a Major Operation in North-West Europe”,51 which arrived at the conclusion that “an assault by a large force in an unlimited operation would only be possible in the Caen Sector”. This sector was described as “Suitable for an assault by a large force provided the East beaches of the Cotentin [the Cherbourg peninsula] are included to secure Cherbourg, and that the assaults on both the Caen and Cotentin Sectors take place simultaneously or closely following one another”. Just before the Combined Commanders were replaced by COSSAC, their planners (an Anglo-American team) produced an outline scheme, never formally approved by their chiefs, known as Operation SKYSCRAPER. This plan envisaged an assault by four seaborne divisions on the beaches between the mouth of the River Orne north of Caen and the estuary of the Vire, and on the southern beaches of the eastern Cotentin. Six other seaborne divisions would be required for the follow-up, and the planners emphasized the importance of having landing craft available for ten divisions simultaneously embarked. Four airborne divisions were also to be used.52 This scheme impressed GHQ Home Forces as a satisfactory tentative basis for planning, but it got a cold reception from the British Chiefs of Staff, who on 30 March decided not to consider its principles.53 This was doubtless due partly to the fact that COSSAC was then already at work, but it is also possible that the Chiefs considered that the Combined Commanders’ planners had asked for
* See Six Years of War, 321-2.
more than it was practicable to provide. It is nevertheless the case that the SKYSCRAPER plan turned out to be very close to the actual plan finally followed in the invasion of Normandy;. considerably closer to it, in fact, than the plan subsequently produced by COSSAC, who was working within the straitjacket of the limited resources prescribed by the Combined Chiefs of Staff. In some other respects the COSSAC plan and the conclusions of the Combined Commanders had much in common. How far General Morgan and his staff profited directly by the work of the Combined Commanders, or how far the same facts simply led the two groups to the same results, it would be difficult to say.
The first task facing COSSAC was the “selection of a lodgement area”. This problem was considered in the light of (a) port capacities; (b) beach capacities; (c) naval considerations; (d) air considerations; (e) German coastal defences; (f) German reserves; (g) Allied forces available. The factor of air cover limited the possible area of assault to the front between Cherbourg and Flushing. Particularly as a result of (b) and (d), the discussion was soon further narrowed down to two main areas: the Pas de Calais and the Cotentin–Caen area. In both these cases, it was noted, subsequent operations would be required to capture additional groups of ports. Of the two, the Pas de Calais offered certain obvious advantages: particularly, a sea crossing of only twenty miles, promising both optimum air support and a very quick turn-around of shipping, which would lighten the burden of naval escort and protection. And the Pas de Calais beaches, though exposed, had a high capacity. But in the Pas de Calais, just because of these advantages, the German defences were at their most formidable; moreover, to expand the lodgement area by capturing more ports would be difficult, since it involved taking distant Antwerp on one side—which meant advancing across a series of water obstacles—or distant Le Havre and Rouen on the other.
The Cotentin-Caen area, on the other hand, had certain clear disadvantages. It was farther from the British airfields and would therefore reduce the amount of support that could be afforded by short-range fighters; while the longer sea voyage would complicate the naval problems. But there were also great advantages. In the Caen sector the German defences, including coast artillery, were light. The beaches there had a very high capacity and were “reasonably sheltered from the prevailing wind”. Finally, the area provided exceptionally suitable ground for the rapid development of forward airfields close to the coast. On balance, therefore, General Morgan and his staff soon reached the same conclusion as the Combined Commanders. The chances of a successful attack and exploitation in the Caen sector were “so much greater ... than in any other that it is considered that its advantages outweigh the disadvantages”.54
COSSAC, however, stipulated that certain conditions were essential if the operation—now called OVERLORD—was to be successful. He emphasized three as particularly vital. One, and the most important, was “that there should be an over-all reduction of the German fighter force between now [30 July 1943] and the time of the surface assault”. The second was that “The German reserves in France and the Low Countries as a whole, excluding divisions holding the coast,
GAF [German Air Force] divisions and training divisions, should not exceed on the day of the assault twelve full-strength first-quality divisions”, and that the Germans should not be in a position to transfer large numbers of first-rate divisions from Russia within the first period of the campaign, or move their reserve divisions against the bridgehead at a rate exceeding three on D Day, five by the second day, or nine by D plus 8. This meant that every effort should be made before the assault to “dissipate and divert German formations, lower their fighting efficiency and disrupt communications”. The third condition was the provision by artificial means of “sheltered waters” off the coast to be assaulted; for in the weather conditions to be expected in the English Channel this was essential if maintenance over the beaches was to be carried on for any length of time. The COSSAC plan envisaged creating two artificial ports by sinking blockships. The MULBERRY harbours in Normandy were ultimately constructed on a much more elaborate basis. “Given these conditions”, wrote General Morgan, “– a reduced GAF, a limitation in the number or effectiveness of German offensive formations in France, and adequate arrangements to provide improvised sheltered waters—it is considered that Operation OVERLORD has a reasonable prospect of success”.*
As we have seen, Morgan had been allowed only three seaborne assault divisions. He planned to land them on a front of roughly 35 miles from north of Caen to Grandcamp, with approximately three tank brigades and an additional infantry brigade group following them in on the same day. A force amounting to two-thirds of a British airborne division (all for which aircraft were expected to be available) was to capture Caen. COSSAC did not propose to attempt any landing on the beaches of the eastern Cotentin. He feared that forces “separated by the low-lying country and river systems in the area of Carentan-Isigny” (the estuary of the Vire) would be exposed to defeat in detail. Indeed, the forces allotted to him were unequal to such an extension. However, he proposed an early attack towards Cherbourg; and he hoped, optimistically, that by D plus 14 about 18 Allied divisions would have been landed, Cherbourg captured and the bridgehead extended some sixty miles inland from Caen.55
COSSAC’s OVERLORD plan was submitted to the British Chiefs of Staff on 15 July 1943. After careful consideration by them, it was sent to Quebec for discussion by the Combined Chiefs of Staff at the QUADRANT conference, which began there on 14 August. The Combined Chiefs, not without much argument as to the precise degree of priority to be given OVERLORD at the expense of the operations in Italy, on 15 August approved Morgan’s outline plan and endorsed the action already taken by the British Chiefs of Staff in authorizing him to proceed with detailed planning and with full preparations.56 This decision was incorporated in the final report of the conference, the target date remaining 1 May 1944. This report also envisaged continuing pressure on the Germans in Italy designed
* The quotations in these two paragraphs are from “Digest of Operation OVERLORD”, a brief summary of the plan prefixed by General Morgan to his report. The “Digest” is published as Appendix A to Gordon A. Harrison, Cross-Channel Attack, and should be consulted for further details.
to create conditions favourable to OVERLORD. Offensive operations against Southern France as a diversion connected with OVERLORD were approved. Mr. Churchill’s favourite JUPITER scheme for action in Norway was still mentioned as a possible alternative in case circumstances rendered OVERLORD impossible. And “highest strategic priority” was given to the Combined Bomber Offensive, designed to effect the “progressive destruction and dislocation of the German military, industrial and economic system, and disruption of vital elements of lines of communication, and the material reduction of German air combat strength”. The broad substance of these decisions, not including the date but including the limiting conditions to which Morgan attached so much importance, was communicated to the Russians when Messrs. Eden and Hull visited Moscow in October.57
No Supreme Commander for OVERLORD had yet been appointed, nor was the appointment made until the last days of 1943. At Quebec the Americans concurred in the British suggestion that Admiral Sir Charles Little (who was later replaced by Admiral Sir Bertram Ramsay) should be Naval Commander and the AOC-in-C. Fighter Command, RAF, Air Marshal Sir Trafford Leigh-Mallory, should be Air Commander.58 About the same time the idea implicit in the decisions of the Casablanca Conference (above, page 14), that the Supreme Commander should be British, was abandoned, since it was clear that over the campaign as a whole the United States forces engaged would be much the larger. Mr. Churchill proposed to Mr. Roosevelt that an American be appointed, and broke to Sir Alan Brooke the news (which seems to have surprised him more than might have been expected) that his earlier offer of the appointment to him could not be implemented.59
The appointment of a Supreme Commander was now up to the President. It was assumed that the post would go to General Marshall. But there was unexpected delay. In October, Churchill urged the importance of a decision. Then the British became aware that the Americans desired that Marshall should command both the North-West Europe and the Mediterranean theatres. There was still to be a commander for each theatre; but above them both—and above the Strategic Air Forces engaged against Germany also—would be the Supreme Commander, whose decisions however would be “subject to reversal” by the Combined Chiefs of Staff. Early in November the British Prime Minister made it clear, informally but in very strong terms, that he would never accept such an arrangement. Nevertheless, at the Cairo (SEXTANT) conference which began later in the month the Americans made the suggestion formally. It was promptly rejected by Churchill and the British Chiefs of Staff in separate memoranda. The British disliked the idea on both national and military grounds. They felt that what Churchill called “the principle of equal status which must be maintained among the great Allies” required that they should have the supreme command in one theatre. They felt also that the Super-Supreme Commander would be, in the words of their Chiefs of Staff, “an extra and unnecessary link in the chain of command”. They undoubtedly considered that a commander possessing such powers would be beyond the control of the Combined Chiefs of Staff, and that
to grant such powers to an American would in effect deprive both the British Chiefs of Staff and the British Government of any effective share in the direction of the war against Germany.60
The Americans now perforce dropped their plan. At the conference (EUREKA) at Teheran at the end of the month, Marshal Stalin, with his usual directness, made it clear that he considered there should be no further delay in making the appointment. A few days later President Roosevelt, obviously feeling, in Churchill’s phrase, that “the command only of OVERLORD was not sufficient to justify General Marshall’s departure from Washington”, appointed General Dwight D. Eisenhower, who as commander in the Mediterranean had given evidence of a special genius for coordinating the efforts of allies.61 The appointment was announced on Christmas Eve, along with that of a British officer, General Sir Henry Maitland Wilson, as Supreme Allied Commander Mediterranean Theatre. On 27 December it was announced that Air Chief Marshal Sir Arthur Tedder would be Deputy Supreme Commander to General Eisenhower.62
Although Naval and Air Commanders-in-Chief had been appointed under the Supreme Commander, no C-in-C was designated for the ground forces. Whether such an appointment was seriously discussed between the British and American authorities at this time does not appear. It was discussed in the Operations Division of the United States War Department and went to the US Joint Chiefs of Staff but no further. The reasons are thus explained by an American official writer: “The concept of a ground commander seemed objectionable on practical grounds. Since the supreme commander would be American, it was considered in September that the ground commander, if there was one, would also have to be American. But, as one officer in OPD pointed out, the ‘ruling factor’ determining in practice the nationality of the ground commander would be the availability of a suitable individual to fill the position. He observed further that no US commander had the battle experience and reputation to challenge the qualifications of the British generals, Montgomery and Alexander, for the job. The conclusion was obvious: it would be impolitic of the Americans to suggest the creation of the job.”63
While it was argued on military grounds that in the later portions of the campaign no intermediate headquarters should be placed between the Supreme Commander and the three Army Groups serving under him,64 nobody suggested that a ground commander was not required for the all-important assault phase. The decision was that this responsibility should fall to the Commander-in-Chief of the (British) 21st Army Group. On 29 November 1943 General Morgan, who had lately returned from consultations with General Marshall, issued a directive65 to the C-in-C 21st Army Group (at this date still General Sir Bernard Paget), informing him that he would be “jointly responsible with the Allied Naval Commander-in-Chief and the Air Commander-in-Chief, Allied Expeditionary Air Force, for the planning of the operation, and, when so ordered, for its execution until such time as the Supreme Allied Commander allocates an area of responsibility to the Commanding General, First [US] Army Group”.* General Eisenhower
* Italics supplied.
indicated a preference that General Sir Harold Alexander should command the British Army Group;66 but the British War Cabinet did not agree, and the appointment of General Sir Bernard Montgomery was announced on 24 December. General Paget became Commander-in-Chief, Middle East.67
The COSSAC Plan is Altered
The appointment of commanders led immediately to alterations in the COSSAC plan of assault. We have seen that Morgan had been allotted very limited resources, and his plan had been constricted accordingly. At Quebec Mr. Churchill had said that “every effort should be made to add at least 25 per cent. strength to the initial assault” and advocated a landing on the “inside beaches” of the Cotentin as well as in the Caen-Grandcamp area.68 Changes were now to be made along these lines.
Whether it was Eisenhower or Montgomery who first suggested these changes “on the military level” is perhaps immaterial; what matters is that the two were in full agreement as to their necessity. General Eisenhower relates that on some apparently unrecorded date late in 1943 he received a “sketchy outline” of the COSSAC plan through an American officer. He thought the front too narrow and the provision for an early capture of Cherbourg inadequate. He saw Montgomery before the latter left the Mediterranean, explained these doubts and authorized him to act as his representative in examining and revising the ground plan.69 On 26 December Mr. Churchill telegraphed the British Chiefs of Staff, “both Eisenhower and Montgomery have expressed themselves entirely dissatisfied with what they have heard of the present plan for OVERLORD, and I gather they will demand a far larger first flight”.70 Montgomery broke his journey to England at Marrakesh on New Year’s Day. There he saw for the first time a copy of the COSSAC plan and immediately told the Prime Minister that the front of assault was too narrow.71 During January 1944 General Montgomery was at work with the naval and air commanders-in-chief on an actual assault plan. This emerged on 1 February as an “Initial Joint Plan” called by the code name NEPTUNE, by which the assault phase of Operation OVERLORD was thereafter known.
The new plan provided for dividing the front of assault between two Armies—the First United States Army on the right, the Second British Army on the left. A total of five British infantry brigades and three US regimental combat teams would land from the sea in the first assault; these formations were directed on D Day by five divisional headquarters, two American, two British and one Canadian. With respect to airborne forces, uncertainty concerning availability of gliders, troop carrier aircraft and crews led to changes in the plan. The original version envisaged dropping one airborne division on the American flank in the beginning, and a second, either there or on the British flank, twenty-four hours later. The ultimate arrangement, when it was found that adequate means would be available, was to drop two airborne divisions on the American flank, and one airborne division on the British flank, during the night preceding D Day. (On
both flanks some glider-borne elements landed only on the evening of D Day.) These final arrangements were the outcome of long and earnest discussion.72
We have seen that the original target date given COSSAC for the operation was 1 May 1944. The Initial Joint Plan postponed the date to 1 June 1944 (subsequently altered by an amendment to 31 May). The postponement was dictated by the chief controlling factor in the administrative situation at this moment—shortage of landing craft. The increase in the assaulting force meant a still larger requirement for craft, and the additional month’s production was important to the plan.
The landing craft problem was closely connected with the much-controverted question of a landing on the Mediterranean coast of France in conjunction with the main landing in Normandy. As we have seen, this project had been approved at Quebec. At Teheran, Marshal Stalin strongly supported it; and that conference’s agreement concerning operations in 1944 began with the provision “that OVERLORD would be launched in May in conjunction with a supporting operation against the South of France on the largest scale that is permitted by the landing craft available at that time”.73 The South of France operation was designated ANVIL.
Through the early months of 1944 there was continued controversy over this operation, in great part arising from the shortage of landing craft for the main attack. The British authorities, however, were doubtful of ANVIL on other grounds. They questioned whether so distant an enterprise would really be of great utility to OVERLORD; and they feared its effect upon the Italian campaign, particularly in the light of the new commitments resulting from the landing at Anzio, carried out on 22 January 1944.* The Americans differed strongly; but it was obviously absurd to persist with ANVIL at the price of reducing OVERLORD, and it became more and more doubtful whether there were landing craft enough for both. Late in March, on General Eisenhower’s and General Wilson’s recommendations, ANVIL, as an attack simultaneous with OVERLORD, was cancelled.74 But the story was not over. The landing on the south coast of France was to take place in due course, though only after much further debate.
Operations before D Day
Operation OVERLORD, properly understood, began long before the first Allied soldier stepped on to the soil of Normandy. For months before D Day the Allied air forces had been engaged in operations which were vital to the success of the invasion.
The Tactical Air Forces—the RAF’s 2nd Tactical Air Force, the US Ninth Air Force, and the Air Defence of Great Britain, formerly known as Fighter Command—were under General Eisenhower’s command, exercised through Air Chief Marshal Leigh-Mallory, from dates late in 1943; though the Ninth was not actually released from its commitment to assist the US Strategic Air Force in Operation POINTBLANK, the combined bomber offensive against Germany, until
* See The Canadians in Italy, 372-75.
10 March 1944. As for the Strategic Air Forces, comprising the RAF Bomber Command and the US Eighth Air Force, they were employed in POINTBLANK under the British Chief of the Air Staff acting as representative of the Combined Chiefs of Staff; and something of a struggle occurred before they were placed under the Supreme Commander. Eisenhower, however, took the view that it was vital that he should have them. OVERLORD, he argued, was no ordinary operation, and in a crisis, when the last ounce of available force was needed, he should not be “in the position of depending upon request and negotiation to get it”. The Combined Chiefs of Staff finally agreed that the Strategic Air Forces should be under his command from 14 April 1944. They were not, however, placed under the Air Commander-in-Chief, Allied Expeditionary Air Force, but directly under the Supreme Commander. Eisenhower delegated to his Deputy, Air Chief Marshal Tedder, the general supervision of all air forces.75
All this did not imply that POINTBLANK was not related to the success or failure of OVERLORD; much the contrary. The strategic air operations carried on under the “Casablanca directive” (above, page 14) and its successors had a great deal to do with creating the conditions which made the invasion possible. At the TRIDENT conference in Washington in May 1943 the Combined Chiefs of Staff agreed upon a carefully-drafted plan for the Combined Bomber Offensive. The six industrial target “systems” which it specified as “principal objectives” were the industries producing submarines, aircraft, ball bearings, oil, synthetic rubber and tires, and military transport vehicles. It also stated as “an Intermediate objective second to none in priority” the fighter strength of the German Air Force.76 The phrase, in the words of an American official writer, had “more force than clarity”;77 but the reduction of German fighter strength was never in practice a secondary part of the programme. It was vital if the bomber offensive itself was to succeed; and, as we have seen, COSSAC specified it as an essential condition of the success of the invasion operation.
The attacks delivered against the German aircraft industry had less effect than might have been expected; indeed, as the result of expansion programmes approved long before, production actually increased tremendously during 1944, acceptances of single-engined fighters by the Luftwaffe from the factories rising from 1531 in January to 3506 in September. (These figures include damaged aircraft returned after repair.)78
[Transcriber note: Footnote reference number 79 is missing in the image PDF.]
But losses in action were large, and pilots were much harder to replace than aircraft. In the first five months of 1944 the German air forces in the West lost no less than 5009 fighters. The Luftwaffe had in fact suffered a decisive defeat. Even at this late date there is no reason to disagree with the basic conclusions stated by General Eisenhower in his report published in 1946: “Our D-Day experience was to convince us that the carefully laid plans of the German High Command to oppose OVERLORD with an efficient air force in great strength were completely frustrated by the strategic bombing operations. Without the overwhelming mastery of the air which we attained by that time our assault against the Continent would have been a most hazardous, if not impossible, undertaking.”80
It was of the first importance to “isolate” the prospective battlefield in Normandy so as to make the approach of enemy reserves as slow and difficult as
possible. Accordingly, a “Transportation Plan” was developed, aimed chiefly at the railway network of North-Western France; an essential part of it was blows at maintenance and repair facilities. The Strategic as well as the Tactical Air Forces participated; this involved for the RAF Bomber Command a switch from its long-established technique of area bombing to the precision bombing of small targets. The attacks on railway objectives began in earnest in March.81 There was much hesitation about the programme, chiefly because of the obvious danger of heavy casualties to French civilians. Mr. Churchill, indeed, invited President Roosevelt to consider the question, obviously with a view to modifying the scheme; but the President declined to interfere.82
Road and rail bridges leading to the battle area were a target-group of special importance. Doubts were entertained as to how effectively aircraft could strike them until a month before D Day, when Ninth Air Force fighter-bombers gave a convincing demonstration on a bridge across the Seine at Vernon. Thereafter the campaign went forward, directed principally against bridges over the Seine, along with some others over the Oise, the Meuse and the Albert Canal. Bridges over the Loire, and in the “Paris-Orléans gap” between Loire and Seine, were (with some exceptions) left alone until after D Day to avoid giving away the secret of our landing area. The Seine bridges would have been equally important had we landed in the Pas de Calais.83 The bridge attacks were eminently successful. The German Commander-in-Chief West’s daily situation report for 28 May84 observed:–
Due to attacks of last four days Seine railway bridges between Paris and Rouen destroyed or impassable. Exception: railway bridge St. Germain [on the western outskirts of Paris]. ... C-in-C West insists on immediate restoration in each case.
In spite of the Germans’ skill and energy in making repairs, there is no doubt that the damage done by these operations and under the “Transportation Plan” as a whole was a most fundamental embarrassment to them and a great contribution to the Allied victory in Normandy.
Specifically military objectives in the assault area, important in connection with the projected landing and subsequent operations, provided the air forces with many targets. Miscellaneous military targets attacked during the preparatory period included ammunition and fuel dumps, camps and headquarters. The “neutralization” of coastal batteries was obviously a vital task which could scarcely be left merely for the final bombardment on D Day itself. We know of 49 such batteries capable of firing on our shipping as it approached the chosen beaches. The Strategic and Tactical Air Forces shared the attack on them, which began in mid-April. Between 10 April and 5 June, there were 2495 sorties of aircraft against coastal batteries in the assault area. Since it was so essential not to reveal the sector where we proposed to land, more than twice as many attacks—6270 sorties in all—were made during this period against batteries outside the area.85
Radar stations were another vital target. The Allied naval and air forces selected those most likely to enable the enemy to detect and interfere with our plans, and a comprehensive campaign was waged against them from 10 May onwards. Again, two targets outside the assault area were attacked for every one
within it. The results were excellent and most valuable. During the night in which the Allied invasion fleet crossed the Channel, the number of enemy radar stations active in the assault area was “only 18 out of a normal 92”, and no station was heard operating between Le Havre and Barfleur.86
In order to reduce the enemy’s air interference to a minimum, it was necessary to “neutralize” his important airfields within 150 miles of Caen. This involved attacking 40 fields; while 59 others in France, Belgium, Holland and Western Germany also received attention with a view both to avoiding any indication of the selected assault area and to interfering with the enemy’s air effort generally. Great damage was done, the effect being to place German fighters under the same handicap as the Allies’ by forcing them to operate from fields distant from the assault area. These measures, along with the attrition of the German fighter force produced by the air battles of the early months of 1944, and the threat to Germany itself represented by the continuing activity of the Allied strategic bombers against the homeland (they took time out from attacks on OVERLORD targets to begin the offensive against German oil plants in May) are the explanation of the extraordinary absence of air opposition to our invasion.87
The Anglo-American Debate
By the end of May, the target-date specified in the Initial Joint Plan, all was in readiness. On 8 May General Eisenhower had accepted 5 June as the actual date for the assault; if the weather that day was unsuitable, considerations of moon and tide would permit postponement to the 6th or 7th (see below, page 88). The operation now imminent was the product of four years of planning and preparation. It was also the outcome of a very long debate on strategy between British and American statesmen and officers. The tortuous story of this controversy, of which we have given some glimpses, is fully told in other books;88 but a brief comment upon it is in order.
From the spring of 1942, when they produced their scheme for an early attack in North-West Europe, the Americans showed themselves consistent believers in the strategy of direct approach, as represented in the concept of a frontal attack across the English Channel. They directed their efforts in a succession of conferences towards obtaining a firm agreement by the British to make such an attack on a definite date, and the earliest date possible. The British showed little enthusiasm for the idea. They put a stop to the dangerous plan for an “emergency” landing in France in 1942, and succeeded in diverting the main Allied effort that year to the Mediterranean. Thereafter, without opposing the basic conception of a cross-Channel attack as the final phase of operations against Germany, they consistently put the case for Mediterranean operations as the expedient of the immediate future. They favoured a flexible and an opportunistic strategy and were reluctant to commit themselves to what their Prime Minister called “lawyers’ agreements”. The Americans saw primarily the great strategic dividends that might result from a successful assault across the Channel. The British were more conscious
of the perils of the operation and its possible cost in human life. Sir Winston Churchill has recorded that while “always willing to join with the United States in a direct assault across the Channel”, he was “not convinced that this was the only way of winning the war” and knew that it would be “a very heavy and hazardous adventure”. The casualties of the Western Front in the First World War were never far from his mind.89
The Americans on their side were, it is evident, distrustful of British policy and suspicious lest the British should not be really loyal to the invasion project. They were afraid that adventures in the Eastern Mediterranean might lead to a Balkan campaign (though Churchill emphasized that he never contemplated sending an army into the Balkans);90 they were afraid of finding themselves fighting for British imperial interests.* In part, this may have been the result of the British strategists’ failure in 1942 to declare frankly at an earlier date their opposition to SLEDGEHAMMER (above, page 6); for this left the Americans feeling, not quite justly, that the British had gone back on an engagement. In part also, doubtless, it had its roots far back in American history. But the Americans need not have worried. In spite of urgings from Field-Marshal Smuts of South Africa, who intensely disliked the OVERLORD scheme,91 the British carried out their undertakings, and by March 1944 their Prime Minister was writing to General Marshall that he was “hardening very much on this operation as the time approaches, in the sense of wishing to strike if humanly possible, even if the limiting conditions we laid down at Moscow are not exactly fulfilled”.92
In the end, the combination of American impetuousness and British caution produced an excellent result. The British prevented the Americans from attacking prematurely in the days when Allied resources were unequal to the task; the Americans spurred the British on to attempt the enterprise when the growth of those resources had produced a situation in which frontal attack was sound policy. The course of the continental campaign which began on 6 June 1944 suggests that the decision to undertake the campaign was an eminently sound one, and that the timing of the assault could scarcely have been improved upon.
* On the US suspicions, see Kent Roberts Greenfield, The Historian and the Army (New Brunswick, NJ, 1954), 52. Mr. Greenfield makes the important point that the tremendous scale of the logistical support required for an operation like the Normandy invasion was a powerful argument for long-term planning and against an opportunistic strategy.