Chapter 23: Securing Peleliu Island
Marine Operations in Southern Peleliu to 22 September
The Need for Reinforcements
The evening of 16 September had found the 1st Marine Division maintaining a beachhead on Peleliu about 3,000 yards long, north to south, and approximately 1,800 yards deep, east to west, with one penetration of 2,000 yards.(See Map VI.) The 1st Marines held the division left in lines not far north of WHITE Beach 1 and at the northwest corner of the airfield area. In the center, the 5th Marines had secured the airfield and had taken some additional ground north and east of that field. On the south, the 7th Marines had only to take Peleliu’s two small southern promontories in order to accomplish its initial missions. The 11th Marines (artillery) was ashore and emplaced, and other reinforcing elements, such as tanks, were also ashore.1
On the morning of 17 September, the 7th Marines resumed its attacks on the south, securing the southern promontories by evening of the 18th. In four days of fighting the regiment wiped out the 3rd Battalion, 15th Infantry, the southern defense force of Colonel Nakagawa’s Peleliu Sector Unit. Meanwhile, elements of the 5th Marines had started a drive eastward to Peleliu’s eastern arm, a drive which culminated in the seizure of that arm against only scattered opposition by evening of the 19th. The Japanese who had originally manned formidable defenses on the eastern arm had evacuated to join the remainder of Colonel Nakagawa’s force in Peleliu’s central ridges. Leisurely mopping up was undertaken on the eastern peninsula from 19 through 23 September. The beaches there were organized for defense against possible counter-landings by Japanese from more northerly islands in the Palaus, and the peninsula was finally designated a defense area. Here assault elements were sent for rest from arduous combat in the central ridges, where, as the 1st Marine Division had already discovered, Colonel Nakagawa’s strongest defenses were located.
The 1st Marines had encountered heavy fire from Japanese defenders along the southern portion of the central ridges on 15 and 16 September, but this opposition was nothing compared to that which the regiment began to meet on the 17th. On the latter day, part of the regiment succeeded in pushing to the top of the first heights at the southern end of the ridge system, suffering heavy casualties as it fought doggedly forward. On the right (east) flank, some marines moved east and later north along East
Road, which ran from the northern part of the airfield up Peleliu’s western arm, hugging the eastern base of the central ridges. Meantime other marines advanced up West Road, which, skirting the southwest nose of the ridge system, ran north along the western base. Neither of these flanking movements went beyond the point at which contact could still be maintained with 1st Marines units fighting in the high ground in the center.
The 1st Marines suffered about 240 casualties during the 17th and in Japanese counterattacks the ensuing night; the 3rd Battalion was reduced to about one third of its original strength; and two companies of the 1st Battalion were practically finished as fighting units. On the other hand, there was some reason for optimism. Progress on the 17th had been measured in hundreds of yards in the rough, high ground at the southern end of the central ridges and strong Japanese resistance had been overcome. Whatever optimism may have existed was not to last too long.
On the 18th, in what the Marine Corps’ history of the operation characterizes as “savage and costly fighting,”2 elements of the 1st and 7th Marines managed to advance more than 500 yards in the center, principally along the ridge lines and hills oriented north and south. But the advance during the day was held up at a group of peaks which seemed at first to form a continuous ridge line that was oriented more east and west than the rest of the Peleliu ridges. Soon, the name Five Sisters came to be applied to a cluster of peaks forming the western side of the terrain feature. A towering hill at its eastern extremity, separated from Five Sisters by a saddle, was designated Hill 300, or Old Baldy. With the 7th Marines held up in the center, at Five Sisters, the units on both sides of the central ridges halted so as not to create exposed flanks.
Similar action continued the next day, when an effort to take Five Sisters proved abortive. One element of the 1st Marines pushed up East Road through the village of Asias and along the eastern base of a long hill known as Walt Ridge. By the morning of the 20th, Company C, after action on Hill 100 at the south end of Walt Ridge, was reduced to 16 men. Companies F and G, hard hit in the center, had to be combined with a squad of men from the 4th War Dog Platoon to form one understrength company. Company A, fighting over high ground on the 1st Marines’ left, was reduced by evening on the 19th to six men who had not been wounded or killed.
On the 20th the 1st Marines had to fall back from Walt Ridge to the southern side of an East Road causeway north of Asias. From this position these right-flank elements faced a 150-yard-wide valley bounded on the right by Walt Ridge and on the left partly by Five Sisters and partly by another ridge designated Five Brothers. This depression, known to the 1st Marine Division as Horseshoe Valley, was renamed Mortimer Valley by men of the 81st Infantry Division who later fought in the same area. In the center, during the 20th, elements of the 7th Marines pushed through strong defenses to high ground at the southwestern corner of a narrow defile which, lying west of Five Sisters, came to be known as Death Valley. Left-flank units of the 1st Marines advanced up West Road a little farther, sending some troops up rising ground from the road to narrow the front of 7th Marines units in the center.
Despite some local advances, by evening on 20 September the 1st Marines had been stopped and, “. . . as an assault unit on the regimental level, had ceased temporarily to exist,”3 having suffered almost 1,750 casualties, well over half its strength. Relief was absolutely necessary, not only because casualties were heavy but also because the survivors were physically exhausted from heat, lack of water, and continuous combat. Elements of the 7th Marines therefore relieved all 1st Marines units except those along West Road.
During the next two days 7th Marines units in the center of the line could gain less than 175 yards; on the right Walt Ridge was again attacked to no avail; and on the left 1st Marines troops fighting along high ground above West Road suffered more casualties. Another attack against Five Sisters was forced back on the 22nd, and at dark containing lines were set up north of Asias, facing Walt Ridge and the mouth of Horseshoe Valley. After a week of extremely arduous combat over incredibly rough and well-defended terrain, the 1st Marine Division had been at least temporarily halted. The division had lost just under 4,000 men. The 1st Marines had been virtually eliminated from the fight (the 1st Battalion, for instance, was reduced to two understrength companies), the 7th Marines were little better off, and the 5th Marines as well as other units, especially Shore Party troops and combat engineers, had not escaped unscathed.
Despite the heavy casualties, there was much on the credit side of the ledger. All of southern Peleliu had been captured; the airfield, the most important single objective, was secure, and division observation planes had begun operations from the field on the 22nd; there was room ashore for supplies and artillery, and all the 11th Marines and the III Amphibious Corps Artillery were ashore and emplaced.4 Finally, the 1st Marine Division enthusiastically estimated, about two thirds of the original Japanese garrison had been killed or rendered ineffective from wounds.
General Rupertus, the division commander, well knew that organized resistance was far from over, and he realized that rooting out the remaining Japanese from the defenses along the central ridges would be a difficult task. One of the division’s objectives, Ngesebus Island and its fighter strip, lying off northern Peleliu, had not yet been captured. Worse still, it was discovered during the night of 22–23 September that the Japanese were reinforcing Peleliu by sending troops in from more northerly islands.
The general had for some time desired to push up the west coast and jump over to Ngesebus, a drive that could outflank the Japanese center of resistance, making it possible to attack from the north as well as the south. This step had not yet been undertaken because of the danger of overextending the division front and because a general breakthrough on the south had been almost momentarily expected. By the 22nd it had become obvious that there was going to be no general break-through. Yet, with Japanese
reinforcements probably coming ashore, the need to move troops north was becoming even more urgent. But the 1st Marine Division could not maintain pressure against known enemy positions, defend all southern Peleliu, and, at the same time, drive north up West Road. Reinforcements were sorely needed.
The Arrival of the 321st Regimental Combat Team.
Whence would come the troops to mount a drive to the north? The III Amphibious Corps Reserve, the 323rd Regimental Combat Team of the 81st Infantry Division, had been committed by Admiral Halsey to the capture of Ulithi and had left the Palaus area on 21 September. The rest of the 81st Division was on Angaur.5 But there, luck was with the 1st Marine Division. By 22 September, resistance on Angaur had been compressed in the northwest pocket, where the 322nd Infantry was to fight for another month.6 The 321st Infantry and its regimental combat team attachments had secured southern Angaur. It had received its baptism of fire, beaten the enemy who opposed it, and played a major role in the capture of Angaur. Its casualties were low and its morale and confidence high. Finally, it was available for reinforcing the 1st Marine Division on Peleliu.7
Calling upon the 321st Regimental Combat Team was not a step which General Rupertus was eager to take. His “. . . reluctance to employ Army troops had become increasingly apparent from the outset. . . ,”8 and the deteriorating situation on Peleliu apparently had done nothing to change his mind. But on the afternoon of 21 September the III Amphibious Corps commander, General Geiger, who had previously been hesitant to impose any specific course of action upon General Rupertus, reluctantly took matters into his own hands. He directed General Rupertus to prepare plans for the evacuation of the 1st Marines from Peleliu and took steps to attach the 321st Regimental Combat Team to the 1st Marine Division. Upon question from General Geiger, General Mueller immediately informed the corps commander that the 321st was readily available for action on Peleliu and for transference to General Rupertus’ operational control on arrival. Brig. Gen. Marcus B. Bell, Assistant Division Commander of the 81st Division, was appointed liaison officer to General Geiger’s headquarters to coordinate details of the 321st’s move.9
The 321st Regimental Combat Team, still under the command of Col. Robert F. Dark, began loading at RED Beach, Angaur, at 0700 on 22 September and at 1200 the next day began unloading over ORANGE Beaches on Peleliu. Debarkation was completed before dark. In addition to the 321st Infantry, Colonel Dark’s command included an engineer company and two medical companies (less two platoons) of organic 81st Division units; an LVT company; an engineer battalion less one company; and the 710th Tank Battalion’s Company A and 81-mm. Provisional Mortar Platoon. There was no artillery initially.
Dividing the Island
The mission assigned by General Rupertus to the 321st Regimental Combat Team was to drive up Peleliu’s western coastal flat north about 1,750 yards from a third phase line to a fourth. (Map IX) The third phase line (the phase lines marked out on Peleliu were oriented generally northwest to southeast) was located about 1,000 yards north of the West Road village of Ngarekeukl, which lay near the southwest corner of the central ridges. The fourth phase line was just north of another West Road village called Garekoru, lying beyond Ngarekeukl.
The 321st’s left was to be anchored on the beach, while its right was to extend east of West Road about 250 yards into the high ground of the main ridges. The 7th Marines were to co-operate in the Army unit’s drive northward by having the 1st and 2nd Battalions maintain pressure against the Japanese from the south-center and pushing the 3rd Battalion along the high ground to the 321st’s right rear. If necessary, the Japanese central pocket was to be bypassed while the Army units advancing northward probed eastward over the ridges for a route by means of which the pocket could be isolated on the north.10
The 321st Infantry Moves North
By 1500 on 23 September the 2nd Battalion, 321st Infantry, had relieved the battered remnants of the 1st and 3rd Battalions, 1st Marines, at the latters’ positions just north of the third phase line.11 The 3rd Battalion, 321st Infantry, drew up behind the 2nd in close support, while the 1st Battalion, designated regimental reserve, assembled on the coastal flat about 500 yards southwest of Ngarekeukl.
As soon as the relief of the 1st Marines elements was completed, the 2nd Battalion, 321st Infantry, sent patrols on a reconnaissance north up the coastal flat to Garekoru. The patrols traveled for the most part along the shore line left of West Road. No Japanese opposition was encountered, but fire was received from enemy positions on the central ridges east of West Road. At Garekoru many land mines, or aerial bombs emplaced as mines, were found, and there were a few defensive positions at the village. These positions were not defended in any strength and at 1700 the reconnaissance patrols reported that the entire area north from the third phase line to Garekoru was generally free of Japanese. Upon receiving this information, General Rupertus ordered the 321st Infantry to push forward as far as possible before dark.
The 2nd Battalion started moving north about 1730 but soon found that the patrol reports were too optimistic. Only the terrain close to the shore had actually been reconnoitered, and this ground had been partially screened from the Japanese on the main ridge lines by a low coral ridge paralleling West Road.12 Left of West Road, beneath the cover of the low ridge, one company was able to advance without opposition. But to the right of the road another company found itself attempting to move over open ground in plain sight of the Japanese on
the central ridges. Advance through the intense small arms and machine gun fire which the Japanese now began to direct at the right company was impossible, and the unit was quickly pinned down. Since darkness was approaching, the company dug in along its line of departure. The left company, which had advanced 100 yards before halting to maintain contact on the right, was withdrawn to establish a continuous defense line at the starting point.
At 0700 on 24 September the 2nd Battalion resumed the advance, after an hour of air and naval bombardment and fifteen minutes of artillery fire, most of which had been directed at the west side of the central ridges and suspected defensive installations near Garekoru. A few casualties were caused by Japanese fire from the central ridges but by noon the battalion’s left had reached a point on West Road south of Garekoru, discovering a trail leading eastward over swampy ground toward the central ridge system. The trail-road junction was held by a few Japanese in prepared positions, but after an exchange of rifle and machine gun fire, the Japanese were killed or driven off. Leaving rear elements to explore the trail to the east, Company G pushed rapidly north through Garekoru to reach the fourth phase line about 1530 hours.
East of West Road, right flank elements of the 2nd Battalion had encountered strong opposition along the low ridge parallel to the road and had finally withdrawn from that ridge to maintain contact with the rest of the battalion. The 3rd Battalion, which had been following the 2nd closely, now made some effort to cover the ridge, occupation of which was important for the protection of the regiment’s flank. But the 3rd Battalion, also under pressure to hurry northward, was deflected off the ridge by Japanese opposition and moved west to follow the route of the 2nd. The 3rd Battalion, 7th Marines, which had initially started out behind the right flank elements of the 2nd Battalion, 321st Infantry, therefore pushed troops over the low ridge. Efforts of the Marine battalion to maintain contact with the 3rd Battalion, 321st Infantry, and to cover the ground which should have been secured by the 321st Infantry, caused the marines some casualties and slowed their advance considerably.
The leading elements of the 3rd Battalion, 321st Infantry, continuing northward, began probing up the central ridges farther north in an attempt to find a route over which troops could move to cut off the Japanese pocket. This effort brought the 321st Infantry’s battalion out into open ground below the central ridges, and it too began to suffer casualties from Japanese fire. One company secured a foothold on the first ridge line east of the road at a point about 600 yards south of the fourth phase line, but most of the battalion dug in for the night along West Road. The 3rd Battalion, 7th Marines, held for the night on the high ground at and immediately north of the third phase line. There was a gap between the Marine and Army battalions during the night.
Meanwhile, patrols of the 2nd Battalion, 321st Infantry, accompanied by Marine and Army tanks, had pushed north up West Road from the fourth phase line almost 2,000 yards to a fifth phase line. Moving forward an additional 200 yards, the advance elements came within sight of Japanese radio installations lying about 600 yards beyond the fifth phase line. Many caves, pillboxes, bunkers, and other defensive installations were observed along West Road and at the radio station, but opposition to the patrol’s advance was negligible and the patrol
withdrew to Garekoru before dark without enemy interference. It appeared that Japanese strength was concentrated in the southern section of the central ridges, and that American forces might be able to move freely over the rest of Peleliu.
While the reconnaissance north was being undertaken, Company E pushed eastward over the trail which had been discovered leading toward the main ridges from a point on West Road just south of Garekoru. This route eastward, soon designated 321st Infantry Trail, led over a swamp and up a narrow, relatively low part of the central ridge system, north of the principal Japanese pocket. If the trail were found to run through the central ridges to East Road, its seizure would isolate the Japanese pocket to the south and cut off enemy routes of reinforcement, escape, and supply.
A knoll designated Hill 10013 dominated the point at which 321st Infantry Trail entered the central ridges, and Company E was ordered to seize the terrain feature before the Japanese to the south could realize their danger and reinforce the area. Moving forward quickly against scattered but stubborn resistance, Company E clambered up the rough slopes of Hill 100 and secured the summit before dark. Late in the afternoon Company I, from its foothold on the west side of the central ridges, pushed its left northeast to establish contact with the right flank of Company E. Companies F and G extended the line back along 321st Infantry Trail to West Road and thence north to Garekoru.
About 1700 a Japanese counterattack at the fourth phase line forced Companies F and G south almost 200 yards. There was, however, no general break-through and much of the ground thus lost was quickly retaken. Japanese troops were observed grouping again north of the fourth phase line about 1800 hours, but the force was broken up by well-placed artillery fire before another counterattack, if any had been planned, could develop. For the rest of the night the enemy was generally quiet all along the 321st Infantry’s front.
The next day the advance was resumed, the first objective being to isolate the main Japanese pocket by pushing across the central ridge system via 321st Infantry Trail. To make all the 321st Infantry available for offensive action, the 3rd Battalion, 7th Marines, extended its left north along the central ridges an additional 300 yards above the third phase line, freeing elements of the 3rd Battalion, 321st Infantry. The 1st Battalion, 7th Marines, was brought up West Road to a position behind the 3rd Battalion, 321st Infantry, to support the latter’s attack eastward and to drive south against the Japanese pocket from 321st Infantry Trail as soon as that trail was secured.
Company E, 321st Infantry, began moving from Hill 100 toward East Road at 0700. Just beyond the hill East Road ran through a saddle dominated on the west by Hill 100 and on the east by a larger height known as Hill B,14 the capture of which was necessary if Peleliu’s western peninsula was to be bisected via 321st Infantry Trail.
Working slowly around the northeast shoulder of Hill 100, Company E reached East Road at a point below that shoulder
about 1030. So far, no Japanese had been encountered, although there had been some rifle and machine gun fire from Hill B. The company now halted, for indications were that Hill B was held in some strength and any further advance would be subjected to plunging fire not only from that hill but also from the ridges to the south and a rough hill mass to the north called Kamilianlul Mountain. Finally, it was decided that Company E would wait until the 3rd Battalion, 321st Infantry, could move up to the heights southwest of Hill B and Hill 100 to provide support of both fire and movement for a continued attack.
But the 3rd Battalion had little success trying to fight over ridge lines (later known to the marines who fought in the same area as Wattie and Baldy Ridges) southwest and south of Hill 100. There was strong enemy fire from many emplacements along the ridges, while the terrain was such that a gap developed between Companies I and L, in the van. Company K was moved into this gap late in the afternoon, but this addition had no effect on the fight. The left of the battalion moved forward barely far enough to maintain contact with Company E, on Hill 100, and the battalion’s right made no appreciable progress. For the first time, the 321st Infantry had come upon defenses similar to those the marines had been attacking at the southern end of the Japanese pocket during the previous week.
North of Garekoru, action during the day was faster and more spectacular. A strong combat patrol comprising infantry, tanks, and LVT flame throwers moved up West Road to destroy installations found north of the fourth phase line the previous afternoon and to extend the area of reconnaissance. The patrol quickly pushed north almost all the way to the fifth phase line, destroying four pillboxes and two large supply dumps, at the same time killing thirty Japanese soldiers while suffering no casualties. The weak resistance encountered by the patrol seemed added proof that remaining Japanese strength was concentrated in the pocket south of 321st Infantry Trail. It now seemed possible to exploit this weakness by sending a strong force forward to secure all of northern Peleliu, seize a staging area for the operation against Ngesebus, and complete the isolation of the southern pocket. Therefore, at 1030, General Rupertus ordered northern Peleliu above the fourth phase line to be divided into two sectors. The 5th Marines were to secure the ground west of Kamilianlul Mountain and East Road while the 321st Infantry, after completing the drive over 321st Infantry Trail, was to take the ground east of the 5th Marines.
The 5th Marines quickly reassembled from scattered defensive positions at southern Peleliu and the island’s eastern arm. Before dark, one battalion had passed through Garekoru, where Company G, 321st Infantry, was still holding, and had reached the Japanese radio station area against light and scattered resistance. The 3rd Battalion, 5th Marines, struck overland from West Road just south of the fifth phase line to set up night defenses on East Road and along the western slopes of Hill 80, an isolated terrain feature lying between Kamilianlul Mountain, on the south, and another hill mass named Amiangal Mountain, located at the northern end of Peleliu. The 5th Marines were ready to begin cleaning up northern Peleliu the next day, 26 September, while
the 321st Infantry was prepared to finish the break-through over the central ridges via 321st Infantry Trail.
The Japanese Reinforce Peleliu
During its attack northward and eastward on 24 and 25 September, the 321st Infantry had encountered Japanese troops who had not been on Peleliu when the 1st Marine Division landed on that island.15 The original Japanese garrison on Peleliu had comprised about 10,500 troops, including at least 4,500 first-line infantrymen of the 2nd Infantry and the 3rd Battalion, 15th Infantry. The latter unit was destroyed by the 7th Marines in southern Peleliu, while the 2nd and 3rd Battalions, 2nd Infantry, had lost over half their strength by 17 September in operations against the 1st and 5th Marine Regiments. As of that date, the 1st Battalion, 2nd Infantry, was probably still relatively intact in the central ridge pocket. Another unit, the 346th Independent Infantry Battalion of the 53rd Independent Mixed Brigade was apparently not committed to action in the south but was stationed on high ground at the northern tip of Peleliu.
By 21 September effective Japanese infantry strength in the central ridges was down to 1,300 men. That, of course, does not paint a true picture of the situation in the central pocket. A trained soldier, well armed, can be tenacious on the defense in such terrain as the central ridges of Peleliu whether or not he be trained for infantry service. There were probably 4,000 Japanese troops (including the 1,300 infantrymen) still firmly ensconced in the central pocket as of 21 September, and there were at least 1,000 more troops in the Amiangal Mountain area at northern Peleliu. Nevertheless, Colonel Nakagawa, commanding the Peleliu Sector Unit, clearly needed reinforcements if he was to hold out much longer. There were perhaps 30,000 Japanese troops in the northern Palaus to draw from, including two battalions of the 59th Infantry, two battalions of the 15th Infantry, and four or five recently organized infantry battalions of the 53rd Independent Mixed Brigade.
But General Inoue had no intention of sending strong reinforcements to Peleliu. That was just one of many islands in the Palaus, and the general feared that the American forces might move northward to Babelthuap and Koror. Moreover, there was a good chance that reinforcements might be destroyed on the way to Peleliu by American air or naval units. General Inoue’s belief that the Americans would move north from Peleliu seems to have been an obvious error in judgment. The III Amphibious Corps had already secured two excellent air-base sites, Angaur and southern Peleliu, where a multitude of planes could be based. From the air-base point of view alone, Babelthuap and Koror would not be needed by the Allies. Moreover, General Inoue must have known that Allied practice throughout the Pacific theaters had been to bypass the most strongly defended Japanese positions whenever possible in favor of seizing more lightly held areas. In the last analysis, General Inoue’s thinking seems to have been wishful. He claimed, after the war, that his defenses at Babelthuap and Koror were much stronger than those on Angaur and Peleliu; he was confident he
could have held the northern islands against a force of the size which the III Amphibious Corps had available in the Palaus.
Whatever his belief, General Inoue, on or about 21 September, reluctantly decided to send one reinforced infantry battalion to Peleliu. The 2nd Battalion, 15th Infantry, on Babelthuap, was chosen for the hazardous trip south. One company16 of the 2nd Battalion left Babelthuap about 2230 on 22 September and reached the northern tip of Peleliu, Akarakoro Point, about 0520 the next morning. At least three of the barges which took these troops to Peleliu were sunk, but the bulk of the company got ashore and most of those whose transportation was lost managed to wade to land over the reefs. The main body of the 2nd Battalion moved to Peleliu on the night of 23–24 September, losing six or seven of fifteen barges.17 Again, however, most of the troops managed to get ashore, although most heavy equipment was undoubtedly lost. During ensuing nights, through 26–27 or 27–28 September, a few more troops landed on Peleliu, most of them probably stragglers who had hidden out on small islands between Babelthuap and their objective. All in all, some 500 fresh Japanese riflemen reached Peleliu. Perhaps 200 more men from an engineer platoon, an infantry gun company, and artillery detachments also arrived, though none of them managed to get heavy equipment or large weapons ashore.
Most of these troops moved south to the main Japanese pocket in the central ridges, and at least one new infantry company occupied defenses in the area where the 3rd Battalion, 321st Infantry, had attempted to hack its way east over the ridges southwest of 321st Infantry Trail. Headquarters and the 6th Company, 2nd Battalion, 15th Infantry, were prevented from moving south by 5th Marines action at Hill 80 and Amiangal Mountain and by operations of the 321st Infantry at Kamilianlul Mountain. Some members of this group probably made their way south by infiltration during the nights following 24 September, but most of them, over 200 strong, probably remained at Amiangal Mountain.
After dispatching the 2nd Battalion, 15th Infantry, and attached units to Peleliu, General Inoue sent no more reinforcements to that island. The 600–700 fresh Japanese who did reach Peleliu could have no effect upon the ultimate outcome of the battle—they could only prolong the operation.
Isolating the Japanese Pockets
Continuing its fight to secure the trail which bore its name, the 321st Infantry encountered elements of the 2nd Battalion, 15th Infantry, on 26 September.18 But before action on that day began, redispositions were made so that the entire 321st Infantry could concentrate on the drive eastward. The 2nd and 3rd Battalions, 7th Marines, took over more ground along the west side of the central ridges north of the third phase line to narrow the front of the 3rd Battalion, 321st Infantry. The 1st Battalion, 7th Marines (less one company), prepared to advance in close support of the 3rd Battalion,
321st Infantry, ready to exploit any break-through the latter unit might achieve.
The 321st Infantry jumped off against Hill B at 0700, with the 2nd Battalion attacking from the west and the 3rd Battalion moving in from the south and southwest. Company I, on the 3rd Battalion’s left and in contact with Company E on Hill 100, was unable to make any progress eastward, and was again pinned down by heavy Japanese mortar and machine gun fire from Wattie and Baldy Ridges, where the attack had stalled the previous afternoon. About 0815 Company L was moved up on I’s right, but it, too, was pinned down before any advance could be made.
The 2nd Battalion, waiting for progress by the 3rd, had not yet started its attack toward Hill B but had assembled in the Hill 100 area. Shortly after 1200, by which time it was apparent that the 3rd Battalion was to make no more progress, a new attack plan was prepared. The 2nd Battalion was directed to press home its attack from the west, using Hill 100 as a line of departure. The 3rd Battalion was to continue pressure and to provide as much fire support as possible from the south and southwest. For the attack from the north a separate group under Capt. George C. Neal, the 2nd Battalion’s S-3, was organized. This unit, known as the Neal Task Force, comprised 45 infantrymen from Company F, 7 medium tanks, 6 LVTs, and 1 LVT mounting a flame thrower.
In preparation for the new attack, the Neal Task Force had started north from the Garekoru area about 1000 hours. It moved up West Road approximately 2,200 yards to the junction of West Road and East Road (the junction was then held by elements of the 5th Marines) and then turned south down East Road. The group moved rapidly southward along the east side of Kamilianlul Mountain to a point within 150 yards of Hill B before any opposition was encountered. Then about 1500, a party of fifteen Japanese made a suicidal attack on the small armored force. All the enemy were quickly killed and the Neal Task Force moved up to provide support fire for the 2nd Battalion’s attack from the west.
Companies E and F had meanwhile maneuvered into positions along ridges and on East Road south and southwest of Hill B; the 1st Battalion had moved north to take over the positions vacated by the 2nd at Garekoru; Company K had relieved Company E on Hill 100. An artillery, mortar, and machine gun concentration was then laid on Hill B, and at 1600 the infantry attack began. Company F struck due east while Company E attacked north. Against stubborn resistance and over very broken, rough terrain, Companies E and F gradually fought their way up the hill. At 1645 advance elements reached the summit and by dark all but a few scattered Japanese riflemen had been cleared from Hill B. The break-through over the central ridge system via 321st Infantry Trail was complete—the principal enemy pocket had been isolated.
North of 321st Infantry Trail, the 5th Marines had divided Peleliu in another place. The 3rd Battalion, 5th Marines, attacking at 0700 on the 26th, secured Hill 80 by 0830 against scattered but resolute resistance. The Marine unit then moved to the eastern shore of Peleliu’s western arm, here indented by a dense mangrove swamp, thereby completing the second division of the island. Late in the afternoon most of the battalion moved back from Hill 80 to a reserve position near the junction of East and West Roads. The unit’s southern flank extended south from the junction along
East Road to Hill 80, where Company I was stationed for the night. Between Company I, 5th Marines, and the 2nd Battalion, 321st Infantry, at Hill B, lay a gap approximately 1,800 yards long through which only the 321st Infantry’s Neal Task Force had passed. In this gap lay 1,500-yard-long Kamilianlul Mountain, held by an unknown number of Japanese and as yet not even reconnoitered by American units.
Southwest of 321st Infantry Trail, operations had not gone so well. Companies I and L, 321st Infantry, directed to provide support for the 2nd Battalion’s attack on Hill B, lost their footholds on the extremely rough ground near Wattie and Baldy Ridges during the afternoon, principally as the result of intense Japanese mortar, machine gun, and rifle fire, against which it was nearly impossible to find cover. Supply difficulties had added to the 3rd Battalion’s problems, for the ground in its zone was so broken that everything had to be laboriously manhandled over razor-back ridgelets, steep slopes, and narrow draws. Finally, in the evening, Company I was able to regain contact with Company K, atop Hill 100, but Company L could not push its way back into the broken terrain on I’s right. Instead, Company L remained at the bottom of the ridges, near West Road, for the night.
Despite the loss of ground in the 3rd Battalion’s area, operations on 26 September were the most successful since the 321st Infantry had been on Peleliu. The island had been cut in two places, one by the 2nd Battalion, 321st Infantry, and one by the 3rd Battalion, 5th Marines; and the rest of the 5th Marines had driven almost to Peleliu’s northern tip. The Japanese were now isolated in two major pockets, the principal one south of 321st Infantry Trail and the other at Amiangal Mountain, on northern Peleliu. To aid the 5th Marines in reducing the latter pocket, General Rupertus ordered the 321st Infantry to send one battalion north from 321st Infantry Trail on the morning of 27 September to secure Kamilianlul Mountain and, if necessary, to push on to Amiangal Mountain.
Northern Peleliu and the Offshore Islands
Amiangal Mountain
The drive to secure northern Peleliu had begun late on 25 September when elements of the 5th Marines had moved up West Road beyond the fifth phase line to the Japanese radio installations.19 At 0900 the next day, the 1st Battalion, 5th Marines, started out from the radio station toward Amiangal Mountain. The northern section of the L-shaped hill mass comprised ridges running generally northeast to southwest for a distance of some 1,000 yards, while the southern section ran northwest to southeast. Having no well-defined ridge lines, the southern leg consisted of four semi-separated knobs, designated from northwest to southeast Hill 1, Hill 2, Hill 3, and Radar Hill, the latter the largest and highest. Located at the edge of the east coast swamp, Radar Hill had contained the principal Japanese radar installations on Peleliu.
On the 26th the 5th Marines secured Hill 2 against determined resistance but marines moving north of the southern leg along West Road were subjected to heavy Japanese fire from Ngesebus Island and the northern leg
and could make little progress. The next day, 27 September, the 5th Marines continued operations at Amiangal Mountain while the 1st Battalion, 321st Infantry, started north from the Hill B area to close the long gap which existed between 321st Infantry Trail and Hill 80. Company C, 321st Infantry, moved north along Kamilianlul Mountain, and Company A, followed by Company B, pushed up East Road, here lying on a narrow strip of land between the mountain and a swamp along the eastern shore of the peninsula. Surprisingly, no enemy opposition of note was encountered on Kamilianlul Mountain, although many abandoned enemy defensive positions were found. Progress during the morning was slowed principally by the rough terrain atop the mountain and by the swamp on the right of East Road. By noon, advance elements of Company C had moved nearly 1,000 yards forward to the highest point of the mountain, 600 yards short of the northern nose. Company A had made a similar advance along East Road.
About 1230 new attack orders were issued. The 1st Battalion was directed to extend its line up East Road from the northern tip of Kamilianlul Mountain to the junction of East and West Roads. Company I, 5th Marines, on Hill 80, was to be relieved, and the Army battalion was to form a defense line running south from the road junction along East Road to Kamilianlul Mountain, maintaining contact on the north with the 3rd Battalion, 5th Marines, at the junction.
Advances during the afternoon were slower, although little opposition was encountered until Company A was pinned down by Japanese fire from a pillbox located at a sharp bend of East Road about 100 yards north of Kamilianlul’s nose. Companies A and C both halted until armor could be brought forward to support an attack against the pillbox and associated lesser defenses. Not waiting for the outcome of this action, Company B passed through Company C and struck up East Road, establishing contact with the 5th Marines near the road junction before dark. It was well that Company B had not waited, for armor could not be brought forward soon enough to support a concerted attack before dark against the pillbox in front of Company A.
During the ensuing night there were apparently some gaps between Companies B and A, on the north and south respectively, and Company C in the center. The latter unit had moved up East Road toward Hill 80 late in the afternoon, but in so doing had lost contact with Company A to the south and did not move far enough north to reach Company B. No American troops occupied Hill 80 during the night. Company C was only as far forward as the southern base of that terrain feature, which had been vacated by Company I, 5th Marines, early in the afternoon.
Meanwhile, the 2nd Battalion, 5th Marines, had pushed up the west side of Amiangal Mountain’s northern leg until halted by fire from caves at the northwest tip of the leg. Since the cave entrances could not be reached by mortar or artillery fire, a novel method of attack was evolved. First, artillery, tanks, and naval fire support vessels threw high explosive and smoke on Ngesebus and other offshore islands from which heavy fire was being directed at the Marine unit. Under cover of this support, five LVT(A)’s moved about 350 yards out on the reef between Peleliu and Ngesebus, from which position they poured fire into the most troublesome cave entrance. This fire was not
unlike that employed by the 41st Infantry Division at Biak, where tanks in LCTs had fired on shore-line ridges. It enabled marines to move around the mountain’s tip to seize Akarakoro Point before dark. The last place where the Japanese could be landed on Peleliu had been captured and suitable positions from which to launch a shore-to-shore operation against Ngesebus had been secured. To the south, other elements of the 5th Marines took Hill 1, on the mountain’s southern leg. The 3rd Battalion, 5th Marines, until now in reserve at the junction of East and West Roads, made preparations to land on Ngesebus on the morrow.
After a night marked by the killing of about 25 Japanese infiltrators in its sector, the 1st Battalion, 321st Infantry, resumed its attack north on the morning of 28 September. Company A, now supported by two medium tanks and some flame throwers, struck out against the pillbox at the East Road curve where the advance had halted the previous evening. Resistance was so stubborn that it was not until 1100 that the reinforced company could overrun the pillbox, but even this achievement did not signify the collapse of all Japanese resistance in the area. Minor installations in the same vicinity and some bypassed positions along the base of Kamilianlul Mountain’s northern nose continued to give trouble and had to be knocked out one by one in a series of infantry-tank-demolitions-flame thrower assaults.
Meanwhile, Company C had found it necessary to fight its way back up Hill 80.20 which Company I, 5th Marines, had left late the previous afternoon. Some Japanese had apparently been overlooked by the 5th Marines’ troops or, more probably, elements of the 2nd Battalion, 15th Infantry, attempting to move south to the principal Japanese pocket, had reoccupied the hill during the night of 27–28 September, when no American units were on the knoll. Whatever the cause of the new resistance, it was almost noon before Company C, 321st Infantry, had resecured Hill 80 and the surrounding ground and had reoccupied the line held by the 3rd Battalion, 5th Marines, two days earlier. By nightfall on the 28th all the ground between Kamilianlul Mountain and the junction of East and West Roads (except for a small pocket in Company A’s zone) had been secured, some of it for a second time.
To the north, the 5th Marines secured Hill 3, on Amiangal Mountain’s southern leg, and isolated more formidable Radar Hill, about 150 yards to the southeast. Other elements of the regiment landed on Ngesebus and Kongauru Islands, offshore, putting a stop to Japanese fire which had been harassing marines working over the northern leg and Akarakoro Point. During the day most of the northern leg was secured, leaving Radar Hill as the only remaining center of organized resistance on Amiangal Mountain. Mopping up along the northern leg and on flat ground to its east was undertaken by 5th Marines elements on the 29th, as was an attack on Radar Hill. A complex cave system on the latter made it impossible to take all the hill before dark.
Preparations had been made during the 29th for the 321st Infantry to relieve the 5th Marines at northern Peleliu and on the offshore islands. The first step in this program was the relief of the 3rd Battalion, 321st Infantry, by elements of the 7th Marines
at the northern side of the principal Japanese pocket, below 321st Infantry Trail. The 3rd Battalion, 321st Infantry, then moved north up Kamilianlul Mountain and East Road, following the routes taken by the 1st Battalion of the same regiment two days earlier. Many bypassed or reoccupying Japanese were found and killed; progress was slow as the 3rd Battalion moved cautiously northward probing into and then sealing each cave entrance it discovered. At nightfall the unit dug in some 200 yards north of 321st Infantry Trail. Meanwhile the 2nd Battalion had relieved Marine units on Ngesebus and Kongauru Islands, while the 1st Battalion had reconnoitered in the Amiangal Mountain area in preparation for the relief of Marine troops there the next day.
On the morning of 30 September, elements of the 5th Marines continued mopping up along Amiangal’s northern leg while other parts of the regiment gained the summit of Radar Hill. At 1000, when the 1st Battalion, 5th Marines, withdrew from the hill, the terrain feature had not been completely overrun. The marines knew that Japanese were still in caves beneath the summit, although the main cave entrances had been blasted shut. Mopping up along the northern leg also had not been completed when, during the afternoon, the 2nd Battalion, 5th Marines, withdrew from that area, while its relief, the 1st Battalion, 321st Infantry, took over. The 5th Marines departed the Amiangal area confident that only a few scattered Japanese riflemen remained there. The regiment reported that it had killed or captured over 1,170 Japanese (it had been estimated on 27 September that there were only 500 in the area) on and around Amiangal Mountain. The 1st Battalion, 321st Infantry, moved into the marines’ vacated positions expecting only minor mopping up to be necessary.
The Army battalion was in for some disillusionment. As Company B, 321st Infantry, moved forward to occupy the four hills along the southern leg of Amiangal Mountain, one platoon was dispatched to secure Radar Hill. When the platoon started up the hill about 1330 hours, it was met by a fierce counterattack from Japanese who had dug their way out of a large cave which the 5th Marines had once blasted shut. The 321st Infantry’s platoon was soon forced back and all Company B got into the action which, lasting until 1500, assumed the proportions of a major fire fight. With the help of artillery, mortar, and tanks, the Japanese were forced back into their cave, and the forward elements of Company B set up night defenses at the base of the hill.
Company A, 321st Infantry, had meanwhile encountered some strong opposition from bypassed Japanese who were holding out along a low ridge which, lying west of West Road, ran north from the junction of East and West Roads to Hill 1 on Amiangal’s southern leg. Some tough fighting ensued, but the ridge was secured before dark and Company A established contact with Company B elements at Hill 1. Company C, moving up to Akarakoro Point and into the flat ground east of Amiangal’s northern leg, had somewhat similar experiences. This area, reported cleared by the 2nd Battalion, 5th Marines, was strongly held by Japanese who had reoccupied prepared positions which the marines had not destroyed. Company C, 321st Infantry, fighting for every foot of ground, killed 40 Japanese in the area between 1500 and dark.
It is certain that the fighting on 30 September at northern Peleliu did not endear the 5th Marines to the 1st Battalion, 321st
Infantry, which had not expected to encounter still organized resistance. But such feelings were prevalent throughout the fighting on Peleliu, where the Japanese continually reoccupied positions which one unit had secured and, sometimes, even resecured. Nor were all similar cases limited to situations in which Army troops took over positions from Marine units. The casualties suffered by the 3rd Battalion, 7th Marines, on 24 September, when it became necessary to move into an area which the 3rd Battalion, 321st Infantry, should have covered on the high ground along West Road between the third and fourth phase lines, had somewhat embittered that Marine unit. Again, the 3rd Battalion, 321st Infantry, mopping up behind the 1st Battalion, 321st Infantry, along Kamilianlul Mountain’s ridges on 29 and 30 September, undoubtedly took a very dim view of the efficiency with which the 1st Battalion had previously “secured” the same area. Other such incidents, involving every conceivable combination and alternation of Marine and Army units, were common.
The difficulties of thorough mopping up in Peleliu’s broken terrain were manifold. Not only did the terrain itself create these difficulties, but the Japanese had also improved upon nature, connecting many caves with underground tunnels and digging multiple entrances in many concealed positions. The enemy not only had a propensity for sneaking back into positions that had been cleared, but he also maintained excellent fire discipline combined with an ability to lie doggo while American troops walked past or even through defensive installations. One day, not a shot would be fired from a Japanese position, but the next day an Army or Marine unit would find its rear fired upon, making it necessary to have a company or even a battalion back-track to capture or recapture the installation.
Under such conditions, the 1st Battalion, 321st Infantry, continued mopping up at northern Peleliu on 1 October, often encountering spasmodic suicidal attacks by small groups of Japanese. Companies C and D, 321st Infantry, killed an additional 40 Japanese on the flat ground near Akarakoro Point, but by dusk they were able to report that area and Amiangal’s northern leg cleared except for a few stragglers. To the south, Company B continued its operations at Radar Hill, reinforced by demolition squads from Company A, 306th Engineers, and the Antitank Company, 321st Infantry. Many cave openings were sealed or resealed and the principal cave entrance, located on the hill’s eastern side, was rediscovered. During the afternoon a platoon of Company B and an engineer demolition squad attempted to move into this entrance but were greeted by a counterattack executed by some 60 Japanese. The hill had to be vacated after about 30 Japanese had been killed and 15 casualties had been suffered by the reinforced Company B platoon. Colonel Dark, the regimental commander, requested reinforcements and, with General Rupertus’ permission, Company G, 321st Infantry, was brought back to the mainland from Ngesebus (where it had relieved Marine units) to help in a new attack on Radar Hill on 2 October.
Early on the 2nd, Company G moved into position along Hill 3 to provide Company B with fire support during the renewed attempt. Tanks were brought into position north of Radar Hill for the same purpose, and a battery of Marine 155-mm. guns stood by to furnish additional fire support as necessary. At 1000 Company B, reinforced
by demolition and flame thrower teams, attacked up the southern and western slopes. Quickly reaching the summit from those directions, the troops began working down the northern and eastern sides, where major resistance was now isolated. After the use of extensive demolitions, the hill was declared secure at 1700. The last vestiges of organized resistance in northern Peleliu had disappeared and mopping up was completed. The 321st Infantry killed at least 175 Japanese during its operations in the Amiangal Mountain area, bringing to approximately 1,350 the known Japanese killed or captured in that region. How many more were sealed in caves or blown to unaccountable bits is unknown, but it seems reasonable to believe that the Amiangal area was defended by nearly 1,500 Japanese, three times the number the 1st Marine Division originally estimated.
Ngesebus, Kongauru, and Other Islands
It is probable that the operations at Amiangal Mountain and Akarakoro Point would not have ended as soon as they did had it not been possible to eliminate the Japanese artillery, mortar, and automatic weapons fire which had been falling on northern Peleliu from Ngesebus and Kongauru Islands.21 With the successful advances made by the 5th Marines and the 1st Battalion, 321st Infantry, in northern Peleliu on 27 September, General Rupertus felt it feasible to undertake the long-delayed assault on Ngesebus.
The 3rd Battalion, 5th Marines, with aerial, naval, and artillery fire support, moved across the reefs from Peleliu shortly after 0900 on 28 September, transported by LVTs and LVT(A)’s. There was little or no opposition to the assault, and fifty Japanese were killed or captured at beach positions before they could recover from the shock of the support fires. Major resistance on Ngesebus centered along a low, rough, coral ridge paralleling the west coast. Despite some tough opposition there, by dark all the island except for a small pocket at the northern tip had been overrun and the Japanese fighter strip had been secured. Elements of the same Marine battalion moved to Kongauru Island, off the eastern side of Ngesebus, secured it against minor opposition, and then moved on to Murphy Island, off the northeast tip of Kongauru.22
The marines continued mopping up on Ngesebus until 1500 on 29 September, when the island was declared secure. An hour later the 2nd Battalion, 321st Infantry, began coming ashore to relieve the marines and complete mopping up. By 1700 hours the relief at Ngesebus had been completed, and Company F, 321st Infantry, had relieved Marine units on Kongauru and Murphy Islands. The next day the 321st Infantry units encountered some resistance from bypassed Japanese along the low ridge at Ngesebus’ western shore. Mopping up there continued simultaneously with the organization of defenses against possible Japanese counterlandings. The 3rd Battalion, 5th Marines, had killed or captured about 470 Japanese on Ngesebus, Kongauru, and Murphy Islands, while the 2nd Battalion, 321st Infantry, had accounted for approximately 100 more on the same islands.
One of the principal reasons for seizing Ngesebus had been to construct a fighter
strip on that island. But the existing Japanese field was found to be surfaced with sand so soft that an airdrome could not be built there without such extensive labor that the results would not be worth the effort, especially with the Peleliu field already operational and the new Angaur field well on its way to completion. The island was therefore abandoned as an airfield site—the principal results of its capture being the elimination of harassing fire on northern Peleliu and the denial of its use to the Japanese as a staging point for troops who might attempt to reinforce Peleliu. At the same time, Ngesebus provided the III Amphibious Corps with a staging base from which minor shore-to-shore operations against other small islands farther north could be launched.
Peleliu at the End of September
On 30 September the Commander, Western Attack Force, Admiral Fort, announced that Angaur, Peleliu, Ngesebus, and Kongauru Islands had been captured and occupied.23 This was true enough to the extent that only some tough mopping up remained to be done in northern Peleliu, at northwestern Angaur, and on Ngesebus and Kongauru. It was also true to the extent that the principal remaining Japanese pocket on Peleliu had been greatly compressed.24 Accomplishments through the 30th of September had cost the 1st Marine Division 5,044 casualties, including 843 men killed, 3,845 wounded, and 356 missing.25 By the same time, the 321st Infantry had lost on Peleliu 46 men killed, 226 wounded, and 7 missing, for a total of 279 casualties.26
The 1st Marine Division estimated that it and the attached 321st Infantry had killed nearly 9,000 Japanese by the end of the month. In addition, 180 prisoners, mostly Koreans or Okinawans, had been taken. Less than 2,500 Japanese were left alive on the island.27 Except for those killed by the 321st Infantry during arduous mopping-up operations at northern Peleliu and on offshore islands, the Japanese left alive on 30 September were concentrated in the central pocket. Against this area the 5th and 7th Marines were to move, relieving elements of the 321st Infantry, while the battered 1st Marines, the 1st Tank Battalion, the two 75-min. pack howitzer battalions of
the 11th Marines, and other smaller Marine units left the island for rehabilitation.28
Thus, by the end of September, Peleliu had been secured—at the cost of some 5,300 American casualties. The Peleliu airdrome, the development of which had been the primary purpose of the seizure of the island, was operational for fighter planes, and the Kossol Passage emergency anchorage was in use. Organized resistance by the remaining Japanese was concentrated at the Umurbrogol Pocket, as the area still held by the Japanese in the central ridges was called.