by Daniel Wrinn
Admiral Nimitz sent a message to General Geiger. He directed him to turn command over to General Mueller’s 81st Division, relieve the 1st Marine Division, and begin mop-up operations and garrison duty on Peleliu.
Mopping up Peleliu
On October 20, General Mueller took responsibility for mop up operations on Peleliu. He described the tactical situation as a siege—and ordered his troops to proceed accordingly.
For six weeks, his two infantry regiments, the 322nd and 323rd, plus the 2nd Battalion of the 321st Regiment, did just that. They used sandbags as an assault device, carrying sand up from the beaches and inching them forward. They pressed closer to enemy caves and dug-in strong points. They used tanks and flamethrowers and even improved on the vehicle-mounted flamethrower. They made a gasoline pipeline from a road-bound gas truck, enabling them (with booster pumps) to launch napalm hundreds of feet into the enemy’s defensive area. They took advantage of the 75mm howitzer on Hill 140 and found other sites to put howitzers and fire point-blank into enemy caves.
To support the growing need for sandbags on ridge-top foxholes, army engineers strung high lines to transport them (along with ammo and rations) up to the peaks and ridge tops. Army troops still took casualties, even with these siege tactics, as they ground down the stubborn Japanese defenses. The Umurbrogol Pocket siege consumed the 81st Division’s full attention and both regimental combat teams until November 27, 1944.
This prolonged siege operation was carried out within twenty miles of a much larger enemy force of 25,000 soldiers in the northern Palaus. The US Navy had the enemy isolated with patrols and bombing from Marine Aircraft Group 11 operating from Peleliu.
As costly and challenging as the Allied advances were, Japanese defenders had similar demanding, and even more discouraging, situations in their underground positions. Sanitation was crude. They had little to no water, rations were nearly nonexistent, and ammunition was even more scarce. As time wore on, some Japanese were given the opportunity to leave the defenses and make suicidal banzai night attacks. Very few were ever captured.
In late November, General Murai suggested in a radio message to General Inoue on Koror to make one final banzai attack for the honor of the empire. Inoue turned him down. By this time, Nakagawa’s only external communications were by radio to Koror. As he’d expected, all local wire communications were destroyed.
Tanks and infantry carefully pressed on in their relentless advance. The 81st Divisions’ engineers improved the roads and ramps leading into the heart of the final Japanese position. Flamethrower and tank attacks steadily reduced each cave position as the infantry pushed its foxhole sandbags forward.
On November 24, Colonel Nakagawa sent his final message to Koror. He’d burned the colors of the 2nd Infantry Regiment and split the remaining fifty-six men into seventeen infiltration parties. They would slip through Allied lines and “attack the enemy everywhere.”
On the night of November 24, twenty-five Japanese soldiers (including two officers) were killed. One soldier was captured the following day. His interrogation, along with post-war records, revealed that General Murai and Colonel Nakagawa committed Seppuku (Japanese ritual suicide by disembowelment) in their command post.
The final two-day advance of the 81st Division was indeed now a mop-up operation. Carefully conducted to eliminate any holdout opposition. By noon on November 27, north-moving units, guarded by other infantry units, met face-to-face with the battalion moving south near the Japanese command post. Colonel Arthur Watson, commanding the 323rd, reported to General Mueller that the operation was over.
The tenacious determination of the enemy was symbolized by the last thirty-three prisoners captured on Peleliu. In March 1947, a small Marine guard attached to a navy garrison on the island found unmistakable signs of a Japanese military presence in a cave.
Patrols captured a straggler, a Japanese sailor who said there were thirty-three Japanese soldiers under the command of Lieutenant Yamaguchi. While the straggler reported some dissension in the ranks, a final banzai attack was still under consideration.
The Navy garrison commander moved his personnel and their dependents to a secure area and radioed Guam for reinforcements and a Japanese war crimes witness. Admiral Michio Sumikawa flew in and traveled by Jeep along the roads near the suspected enemy positions. Through a loudspeaker, he recited the existing situation.
No response. The Japanese sailor who’d been captured earlier went back to the cave armed with letters from Japanese families and former officers on the Palaus, informing the holdouts that the war was indeed over.
On April 21, 1947, the holdouts surrendered. Lieutenant Yamaguchi led a haggard twenty-six soldiers to a position of eighty battle-dressed Marines. Yamaguchi bowed and handed over his sword to the on-scene US Navy commander.
Conditions on Peleliu
Robert “Pepper” Martin from Time magazine was one of the few civilian correspondents who chose to share the fate of the Marines on Peleliu. He wrote the following account: “Peleliu was a horrible place. Suffocating heat and sporadic rain—a muggy rain that brings no relief—only more misery. Coral rocks soak up heat during the day, and it’s only slightly cooler at night.
“The Marines were in the finest possible physical condition, but they wilted on Peleliu. By the fourth day, there were as many casualties from heat as from wounds. Peleliu was worse than Guam in its bloodiness, climate, terror, and tenacity of the Japs. The sheer brutality and fatigue has surpassed anything yet seen in the Pacific, indeed from the standpoint of troops involved in the time taken to make the island secure.
“On the second day, the temperature had reached 105 degrees in the shade. There was little to no shade in most places where the fighting was going on, and arguably there was no breeze anywhere. It lingered at that level of heat as days dragged by (temperatures were recorded as high as 115 degrees).
“The water supply was a serious problem from the start. While this had been anticipated, the solution proved less complicated than expected. Engineers discovered productive wells could be drilled almost anywhere on low ground. Personnel semi-permanently stationed at the beach found that even shallow holes dug in the sand would yield a mildly repulsive liquid that could be purified for drinking with halazone tablets.
“It continued to be necessary to supply the assault troops from scoured out oil drums and 5-gallon fuel cans. But steaming out the oil drums didn’t remove the oil, which resulted in many troops drinking water and getting sick. When the captains of the ships in the transport area learned of this and the shortage of water, they rushed cases of fruit and fruit drinks to the beaches to ease the problem.
“The water situation was a problem for troops operating on the relatively open and level ground. Once the fighting entered the ridges, just traversing the difficult terrain without having to fight caused the debility rate to shoot up quickly. An emergency call was sent to all the ships offshore—requisitioning every available salt tablet for the 1st Marines.”
The statement that heat casualties equaled wound casualties was misleading. Most evacuated troops were returned to duty after a day or two of rest. Their absence from the front lines did not permanently impair the combat efficiency of their units. But these several cases strained the already overburdened medical core.
III Amphibious Corps
The III Amphibious Corps commander, General Roy Geiger, was responsible for planning the seizure of the southern Palaus (Peleliu, Ngesebus, and Angaur). But Geiger and his staff were distracted during these critical planning weeks with the liberation of Guam on August 10.
The Guam operation took a month longer than planned. Someone else needed to plan the assault for the operation in the Palaus. A temporary headquarters, X-Ray Corps, under General Julian Smith was formed. The two main assaults of the southern Palaus campaign were assigned to the Army’s 81st Infantry (Angaur) and the 1st Marine Division (Peleliu-Ngesebus). The 81st Division was also tasked with placing one regimental combat team
as a core reserve.
While this separation of division level planning was convenient, it caused a gross imbalance of force allocation, neither recognized nor corrected as plans progressed. The 1st Marine Division had nine infantry battalions (8,000 Marines) to attack over 10,000 enemy defenders on Peleliu. General Mueller’s 81st Infantry Division had six infantry battalions (5,400 soldiers) allocated to attack 1,500 Japanese defenders on Angaur.
The circumstances and the terrain between the two islands were also imbalanced. Peleliu was much larger and had a more complex landscape. The defensive fortifications were far more developed, and it offered fewer predictable landing beaches than on Angaur.
Only the later rapid shifting of plans accounted for such force allocation imbalances not being corrected at the Corps or Expeditionary Troops level. The effect of these imbalances was magnified on September 17. Higher-level changes in these plans (naval decisions) took away all the III Amphibious Corps reserves.
Divisions and Commanders
Operation Stalemate would be conducted by two divisions, one from the Marines, and one from the Army. In the Pacific since mid-1942, the 1st Marine Division was a combat-tested veteran organization that launched the first offensive landing in the Pacific on Guadalcanal.
After a brief rest and recovery in Australia, and training newly joined Marines, the division made its second amphibious assault at Cape Gloucester (Operation Backhander) on New Britain on December 26, 1943. When the 1st Division landed on Peleliu on September 15, 1944, its regiments had officers and enlisted Marine veterans from both landings and fresh troops ready to fight. Before World War II ended, the 1st Marine Division took part in one last battle: Operation Iceberg and victory on Okinawa.
General William Rupertus
General Rupertus commanded the 1st Marine Division during their time on Peleliu. He’d been with the division since the beginning of 1942. As a brigadier general, he was General Vandegrift’s assistant division commander during the Guadalcanal campaign.
He took command of the division at the start of Operation Backhander (battle for Cape Gloucester on New Britain) on December 26, 1943. Rupertus was commissioned in 1913 and commanded a Marine ship’s detachment in World War I. Following the Great War, he was assigned to duty in China and Haiti. After the Peleliu campaign, he was made Commandant of the Marine Corps schools in Quantico. On March 25, 1945, the general died of a heart attack while still on active duty, aged fifty-five.
General Paul Mueller
General Mueller commanded the 81st Division and was a graduate of the West Point class of 1915. He commanded an infantry battalion in France in World War I and during the interwar period had several infantry commands and staff billets. In August 1941, he took command of the 81st at Fort Rucker, Alabama, and trained extensively until his division was called to battle in Angaur and Peleliu.
General Mueller served on active duty until retiring in 1954. He died ten years later on September 25 at seventy-one years of age.
Army’s 81st Infantry Division
The Wildcats formed in August 17 at Camp Jackson, South Carolina. They saw action in France at the Argonne in World War I. They were deactivated at the end of the war. In June 1942, the 81st was reactivated and sent to several Pacific training bases before their first combat assignment on Angaur.
After successful operations on Angaur, they relieved units of the 1st Marine Division on Peleliu. Once Peleliu was secure, the Wildcats trained for Operation Olympic—the invasion of Japan. But the Japanese surrendered after two atomic bomb attacks. Instead of invading Japan, the 81st became an occupying force. On January 30, 1946, the 81st Infantry Division was once again deactivated.
Japanese Fighting Tactics
After the December 1941 surprise attacks, Japanese military planners believed they could quickly secure an Asian empire in the Pacific. Japan would defend her territories until the bitter end. The Empire of Japan would tire and bleed out the Allies before negotiating Japanese dominance in the Pacific.
This strategic concept was in line with the medieval Japanese code of bushido. The Japanese believed in their army’s moral superiority over lesser races. This led the Japanese to expect their 19th-century banzai tactics would bring them success. Experience and expectations clashed until their 1942 encounters with the Allies, particularly in the Solomon’s. It took several confrontations with the Allies to learn that modern infantry weapons and tactics would defeat them.
To Allied troops, these Japanese misconceptions were disturbing but cost-effective. It was less costly and easier to mow down banzai attacks than dig stubborn defenders out of fortified positions.
By the spring of 1944, these hard lessons had been understood in the highest levels of Japan’s Army Command. When General Tojo directed General Inoue to defend the Palaus deliberately and conservatively, he ordered Japanese troops to dig in and hunker down, making the final defense a costly and bloody affair.
Naval Gunfire Support
In many of the 1st Division Marines’ earlier operations (especially on Guadalcanal) they were on the receiving end of naval gunfire. At Cape Gloucester, the character and disposition of the Japanese defenses didn’t call for extensive pre-landing fire support, nor did following operations ashore.
The naval gunfire Guadalcanal veterans were exposed to often damaged planes and installations onshore. Its effect on the dug-in Marines was sobering and scary, but rarely destructive.
During the planning for Peleliu, division staff had no trained naval gunfire planner. When one arrived, he was hindered by a cumbersome communications link back to higher headquarters.
General Holland M. Smith’s FMF (Fleet Marine Force) in Honolulu would provide essential targeting information for the division’s plan. The FMF would also plan and allocate available gunfire resources to the targets deemed necessary by the division staff planners.
This preoccupation with the ongoing Marianna’s campaigns and illness of Admiral Jesse Oldendorf, the naval gunfire support group commander, further limited and constrained preparations. Heavy enemy ammunition expenditures in the Marianas also reduced the available ammunition for the Peleliu operation.
During the delivery of Allied preparatory fires, there was no Japanese response. This persuaded Oldendorf to report all known targets destroyed and to cancel any further preparatory fires scheduled on D +3. An unintended benefit of this change in naval gunfire resulted in more shells being available for post-landing support.
But the costly effect of this inadequate naval gunfire support was that the flanking positions north and south of the landing beaches were destroyed. The selection of naval gunfire targets could have been done more thoroughly. Colonel “Chesty” Puller, the 1st Marines commander, specifically asked for the destruction of positions dominating his landing on his division’s left flanks.
This failure was paid for in blood, bravery, and time during the battle for the Point.
After D-Day, there were several instances of well called and delivered naval gunfire support. Night illuminations during September 16 and the destruction of two significant blockhouses were effective support for the Ngesebus landing.
Reef-crossing Tactics
Peleliu’s coral reef would not permit landing craft within 700 yards of the beach, so the landing craft deposited tanks at the reef’s edge. The depth of the reef’s edge allowed the tanks to operate in most areas without being submerged.
A plan was devised to form tanks into small columns, each led by an LVT. As long as the amphibious tractor was grounded on the reef, the tanks could follow. When an LVT encountered a depth that floated it, tanks were halted while the amphibious tractor felt for a more suitable, shallow path. This brought the tanks onshore in small columns as quickly as possible. This tactic was crucial for timely employment of armor onshore before D-Day was over.
Two other reef crossing innovations were used on D-Day. Several amphibious trailers were towed behind landing craft, and later, at the reef’s edge, they were towe
d in by the LVTs. Once onshore, trucks pulled them the rest of the way in. This allowed for vital supplies to be brought into points in the rear of the fighting.
Newly available cranes were placed on barges near the reef’s edge. They lifted nets full of ammunition and other essential supplies from boats to tractors at the transfer lines. Crawler cranes were landed early and positioned by the shore party to lift net loads from LVTs to trucks for a swift forward delivery.
Conquest of Peleliu
Was the seizure of Peleliu necessary?
What were the advantages to the US war effort from securing Peleliu?
It assured the absolute domination of all the Palau Islands. It also added to the security of General MacArthur’s right flank as he continued westward with his Philippines campaign. Within the Palaus group, the conquest destroyed enemy facilities that survived Admiral Mitscher’s destructive strike in March 1944.
Securing Peleliu also ensured a total denial of support to Japanese forces from the submarine base at Koror. Reducing the already waning enemy submarine capability east of the Philippines.
