Guam in World War II


Marines on Guam
Marines on Guam


Excerpts from "LIBERATION: Marines in the Recapture of Guam" by Cyril J. O'Brien Marines in World War II Commemorative Series



War in the Pacific National Historical Park is located on the tropical island of Guam, approximately 13 degrees north of the equator and about 3,300 miles southwest of Hawaii. On Guam there is an embracing "hafa adai" attitude that welcomes visitors and makes the island a friendly travel destination and a unique place to live in the United States.

While Guam is only 212 square miles, the island is rich in history. Only hours after Pearl Harbor was attacked, the Japanese began aerial bombings on Guam. After two days of strafing, the Japanese came ashore and hours later the naval governor surrendered the American territory. The island remained under Japanese control for 31 months until July 21, 1944 when the United States returned and liberated the island. Many lives were lost and the suffering was great for all those involved in the battles on Guam and throughout the Pacific theater. In order to remember the United States and Guam's involvement in World War II, War in the Pacific was established in 1978 to commemorate the bravery and sacrifice of those participating in the campaigns of the Pacific Theater of World War II and to conserve and interpret outstanding natural, scenic, and historic values and objects of the island of Guam

While the park is most noted for its historical resources, the warm climate, sandy beaches, and turquoise waters beckon visitors and residents to discover and rediscover the island's history, environment, and recreational opportunities.

Imperial Japanese Invasion

The Japanese landed about 400 troops of the 5th Defence Force from Saipanon Guam on 10 December 1941 at Dungcas Beach, north of Agana. They attacked and quickly defeated the Insular Force Guard in Agana. They then advanced on Piti, moving toward Sumay and the Marine Barracks. The principal engagement took place on Agana's Plaza de Espana at 04:45 when a few Marines and Insular Force Guardsmen fought with the Japanese naval soldiers. After token post invasion resistance, the Marines on Governor McMillin's orders surrendered at 05:45. Governor McMillin officially surrendered at 06:00.A few skirmishes took place all over the island before news of the surrender spread and the rest of the island forces laid down their arms. The American patrol boat YP-16 was scuttled by means of fire during the event and YP-17 was captured by Japanese naval forces. An American freighter was damaged by the Japanese.

In the meantime the Japanese South Seas Detached Force (about 5,500 men) under the command of Major-General Horii made separate landings at Tumon Bay in the north, on the southwest coast near Merizo, and on the eastern shore of the island at Talafofo Bay.

The governor of Guam, Captain George J. McMillan (the island governor was always a U.S. Navy officer), aware that he could expect no reinforcement or relief, decided to surrender the territory to Japanese naval forces. Foremost in his mind was the fate of the 20,000 Guamanians, all American nationals, who would inevitably suffer if a strong defense was mounted. He felt "the situation was simply hopeless." He sent word to the 153 Marines of the barracks detachment at Sumay on Orote Peninsula and the 80-man Insular Guard to lay down their arms. Even so, in two days of bombing and fighting, the garrison lost 19 men killed and 42 wounded, including four Marines killed and 12 wounded.

Operation Forager

In late 1943, both the Joint Chiefs of Staff (JCS) and, later, the Combined Chiefs of Staff (CCS) agreed to the further direction of the Pacific War. General Douglas MacArthur, commander of the Southwest Pacific Area, was to head north through New Guinea to regain the Philippines. Admiral Chester W. Nimitz, Commander in Chief, U.S. Pacific Fleet, and Pacific Ocean Areas (CinCPac/CinCPOA), proposed a move through the Central Pacific to secure a hold in the Marianas. The strategic bombing of Japan would originate from captured fields on Guam, Saipan, and Tinian. The new strategic weapon for these attacks would be the B-29 bomber, which had a range of 3,000 miles while carrying 10,000 pounds of bombs. The code name of the Marianas operation was "Forager." The Central Pacific drive began with the landing on Tarawa in November 1943, followed by the landings in Kwajalein Atoll on Roi-Namur, Eniwetok, and Kwajalein itself.

In January 1944, Admiral Nimitz made final plans for Guam, and selected his command structure for the Marianas campaign. Accordingly, Admiral Raymond A. Spruance, the victor at Midway, was designated commander of the Fifth Fleet and of all the Central Pacific Task Forces; he would command all units involved in Forager.

Ashore in the North

Troops of the 3d Marine Division landed virtually in the lap of the Japanese island commander, General Takashina, whose U-shaped cave command post, carved out of a sandstone cliff, overlooked the Asan-Adelup beachhead. The looming heights dominated the beaches, particularly on the left and center, where the 3d and 21st Marines were headed for the shore.

W-Day, 21 July 1944, opened as a beautiful day, .but it soon turned hazy as the violent clouds of smoke, dust, and fire spiraled skyward. At 0808 an air observer shouted into his microphone: "First wave on the beach." At 0833, the same airborne announcer confirmed the battle was on, with: "Troops ashore on all beaches."

The Southern Beaches

In the south at Agat, despite favorable terrain for the attack, the 1st Brigade found enemy resistance at the beachhead to be more intense than that which the 3d Division found on the northern beaches. Small arms and machine gun fire, and the incessant fires of two 75mm guns and a 37mm gun from a concrete blockhouse with a four-foot thick roof built into the nose of Gaan Point, greeted the invading Marines as the LVTs churned ashore. The structure had been well camouflaged and not spotted by photo interpreters before the landing nor, unfortunately, selected as a target for bombing. As a result, its guns knocked out two dozen amtracs carrying elements of the 22d Marines. For the assault forces' first hours ashore on W-Day on the southern beaches, the Gaan position posed a major problem.

The assault at Agat was treated to the same thunderous naval gunfire support which had disrupted and shook the ground in advance of the landings on the northern beaches at Asan. When the 1st Brigade assault wave was 1,000 yards from the beach, hundreds of 4.5-inch rockets from LCI(G)s (Landing Craft, Infantry, Gunboat) slammed into the strand. It would be the last of the powerful support the troops of the brigade in assault would get before they touched down on Guam.

Fonte Ridge

The two days of fierce fighting on the left of the 3d Division's beachhead in the area that was now dubbed Bundschu Ridge cost the 3d Marines 615 men killed, wounded, and missing. The 21st Marines in the center held up its advance on 22 July until the 3d Marines could get moving, but the men in their exposed positions along the top of the ridge, seized so rapidly on W-Day, were hammered by Japanese mortar fire, so much so that Colonel Butler received permission to replace the 2d Battalion by the 1st, which had been in division reserve. The 9th Marines met relatively little resistance as it overran many abandoned Japanese positions in its drive toward the former American naval base at Piti on the shore of Apra Harbor. The 3d Battalion, after a heavy barrage of naval gunfire and bombs, assaulted Cabras Island in mid-afternoon, landing from LVTs to find its major obstacle dense brambles with hundreds of mines.


The 22d Marines had driven up the coast from Agat in a series of hard-fought clashes with stubborn enemy defenders. The 4th Marines had swept up the slopes of Mount Alifan and secured the high ground overlooking the beachhead. By the 25th, the brigade was in line across the mouth of Orote Peninsula facing a formidable defensive line in depth, anchored in swamps and low hillocks, concealed by heavy undergrowth, and bristling with automatic weapons.

The 77th Infantry Division had taken over the rest of the southern beachhead, relieving the 4th Marines of its patrolling duties to the south and in the hills to the east. The division's artillery and a good part of the III Corp'39; big guns hammered the Japanese on Orote without letup. Just in case of enemy air attack, the beach defenses from Agat to Bangi Point were manned by the 9th Defense Battalion. There were not too many Japanese planes in the sky, and so the antiaircraft artillerymen could concentrate on firing across the water into the southern flank of the enemy's Orote positions. On Cabras Island, the 14th Defense Battalion moved into position where it could equally provide direct flanking fire on the peninsula's northern coast and stand ready to elevate its guns to fire at enemy planes in the skies above.

The 5,000 Japanese defenders on Orote took part in General Takashina's all-out counterattack and it began in the early morning hours of 26 July. The attackers stormed vigorously out of the concealing mangrove swamp and the response was just as spirited. Here, as in the north, there was evidence that some of the attackers had fortified themselves with sake and there were senseless actions by officers who attacked the Marine tanks armed only with their samurai swords. There were deadly and professional attacks as well, with Marines bayoneted in their foxholes. There was one attendant communications breakdown obliging Captain Robert Frank, commanding officer of Company L, 22d Marines, to remain on the front relaying artillery spots to the regimental S-2 and thence to brigade artillery.

Securing the Force Beachhead Line

With the breakthrough at Fonte and failure of Takashina's mass counterattack, the American positions could be consolidated. The 3d and 21st Marines squared away their holds on heights and the 9th Marines (July 27-29) pushed its final way up to Mount Alutom and Mount Chachao.

The most serious resistance to occupying the Mount Alutom-Mount Chachao massif and securing the Force Beachhead Line (FBHL) across the hills was a surprisingly strong point at the base of Mount Chachao. Major Donald B. Hubbard, commanding the 3d Battalion, 9th Marines (replacing Lieutenant Colonel Asmuth, wounded on W-Day), called down artillery, and, after the barrage, his Marines attacked with grenades and bayonets. They destroyed everything that stood in their path. When that fight was over, Major Hubbard's battalion counted 135 Japanese dead. As the assault force pushed up these commanding slopes, the Marines could spot men of Company A of the 305th Infantry atop Mount Tenjo to the west. Lieutenant Colonel Carey A. Randall's 1st Battalion, 9th Marines, then moved up and made contact with the Army troops. Originally, Mount Tenjo had been in the 3d Division zone, but General Bruce had wanted to get his men on the high ground so they could push ahead along the heights and not get trapped in the ravines. He also wanted to prevent the piecemeal commitment of his division and to preserve its integrity.

The Attack North

III Corps's Geiger knew Obata's probable route of retreat and drew up a succession of objectives across the island which would incrementally seize all potential enemy strong points. Jump-off for the drive north was 063031 July with the 3d Marine Division on the left and the 77th Infantry Division on the right, dividing the island down the middle. The Marine zone would include the island capital of Agana, the Japanese airfield at Tiyan, Finegayan, and the shores of Tumon Bay. The 77th would have Mount Barrigada, Yigo, and Mount Santa Rosa in its zone. The 1st Marine Brigade relieved the 77th Division of the defense of the southern portion of the FBHL and would continue to patrol the southern half of Guam. As the Corps attack moved northward and the is land widened, the brigade would eventually take part in the drive to the extreme north coast of the island.

Beginning of the End

On 4 August, the new frontlines and scheme of maneuver were being set up to keep pressure on General Obata and his holdouts, and make a place for General Shepherd and his brigade. During the afternoon, the brigade reached its northern assembly area and General Shepherd set up his CP near San Antonio. In the final advance north, the brigade would be on the left with its inland flank within a mile of the western beaches. The 3d Division would be in the center deploying its units on a three-regiment front which would swerve to the east to take in the whole northern end of the island and as well support the 77th Division.

The Japanese now faced an overwhelming number of attack forces. And there would be plenty of help from the sea and from the air. General Bruce's soldiers made the principal corps drive to destroy the remaining Japanese and attacked Mount Santa Rosa. Priority of fires of corps artillery, air support, and ships gunfire was now given to the Army. These new arrangements were to take effect on 7 August.

Making new strides to end the campaign, the 3d and 21st Marines progressed handily but the 9th Marines kept running into dense jungle that was such a tangled mess that tanks passed each other 15 feet apart without knowing the other was there. The division accelerated its advance in battalion columns. On 6 August, it had progressed 5,000 yards along the road to Ritidian Point, the end of the island and the end of the battle for Guam. As that evening fell, the 3d Division was in visual contact with the 77th Infantry Division, wherever the all-encompassing jungle allowed.

Meanwhile, heavy Seventh Air Force bombing as well as artillery and naval shelling of enemy areas had been going on for days. Night fighters were now assigned to support the advance, so even darkness afforded the Japanese no protection. By that same 6 August, the defense line that General Obata had set across Guam had been shattered and overrun. Only isolated pockets now existed before Santa Rosa.

No American commander could say on 7 August when the fight for Guam would be over. General Bruce in his attack first to Yigo and then Santa Rosa would have a relatively fresh regiment, the 306th, which had come up from the south where it had patrolled with the brigade. It was in contact with the 9th Marines on the division boundary. Colonel Douglas C. McNair, 77th Division chief of staff, was there, too, seeking a site for a division CP and was killed by a sniper. Colonel McNair's father, Lieutenant General Leslie J. McNair, was killed in France 12 days earlier during an American bombing raid.

The attack on Mount Santa Rosa began at noon, 7 August. Behind the rumble of artillery and rattle of tanks, answered in kind by the enemy, the 77th took Yigo, the door to Santa Rosa, and continued General Bruce's wheeling maneuver. Bulldozers blazed trails, and tanks and infantry overran machine gun positions. The 77th was dug into positions on the night of 7-8 August ready for the final attack on the mountain. The expected big Japanese counterattack still did not come. The rapid advance of the Americans accompanied by heavy artillery support likely forestalled that forlorn hope.

Two regiments, the 305th and 307th, proceeded rapidly on 8 August. By 1240, the northern half of Mount Santa Rosa was in American hands, and the troops moved to secure the rest of the mountain. By 1440 the Army had reached the cliffs by the sea and could look right down to the ocean. The 306th infantry had also completed an enveloping move to take the northern slopes of Mount Santa Rosa.

Only 600 enemy bodies were found after the two-day fight for Yigo and Santa Rosa. Yet, estimates of the enemy personnel at Santa Rosa had been as high as 5,000. So this meant that enemy troops in significant number now infested the jungled terrain everywhere on Guam. Worse, some enemy tanks were also unaccounted for. Enemy survivors of the Mount Santa Rosa battle kept drifting into the 9th Marines lines on the Army flank, slowing the regiment's advance. Sharp-eyed Marines noted more than a smattering of enemy movement near a particular hill in the Army zone. This was believed to be the command post area of General Obata.

The 3d Marines on the left of the division's zone had progressed with the same occasional enemy opposition. A 19-man roadblock held up the Marines, but was taken out quickly. Searching a corridor between the 3d and the 9th Marines, the 21st Marines came upon the bodies of 30 Guamanians near Chaguian. They had been beheaded.

The brigade had it a little easier on the far west, for it found negligible resistance as it advanced along fairly good trails. On 8 August, a patrol of the 22d Marines reached Ritidian Point, the northernmost point of the island. Moving along a twisting cliff trail to the beach, the Marines encountered less-than-aggressive Japanese defenses which they quickly overcame. General Shepherd's 1st Provisional Marine Brigade had the distinction of being first to reach both the southernmost point of the island in the early days of the campaign and the northernmost section of Guam at Ritidian Point at this time.

General Shepherd's Marines began vigorously patrolling the area it they occupied, but found few Japanese. As a result, General Geiger reduced the amount of naval gunfire placed on the area, while Saipan-based Seventh Air Force P-47's made their last bombing and strafing runs on Ritidian Point. The 22d Marines was down below the cliffs at Ritidian, scouring along the beaches where there are many caves. The 4th Marines was on the north coast at Mengagan Point and tied by patrols to the 22d Marines. At 1800, 9 August, General Shepherd declared organized resistance had ceased in his zone.

It was not so easy for the 3d Marines. On the night of 8-9 August near Tarague, the regiment was hit by a last-resort Japanese mortar and tank attack. Marine antitank grenades and bazooka rockets were wet and ineffective and the Japanese blazed away with impunity and then ducked back into the woods. Amazingly, when Major William A. Culpepper, commanding the 2d Battalion (Lieutenant Colonel de Zayas had been killed on 26 July), counted heads, he found that he had suffered not a single casualty.

Patrols of the 9th Marines advanced to Pati Point, the northeast projection of the island. Intelligence sources then reported to Colonel Craig that a mass of Japanese (maybe 2,000) troops were holed up at Savana Grand, a wild tract of jungle, coconut trees, and high grasses near the coast. Colonel Craig did not want to risk casualties so close to the end of the campaign, so the artillery supporting the 9th Marines fired a total of 2,280 rounds. The few Japanese survivors were either killed or became prisoners. The final American positions formed along the coast. By nightfall of 8 August, Colonel Craig's Marines could wave to the soldiers of the 306th patrolling to their south.

General Geiger was not ready to declare Guam secure until a pocket of tanks still existing in the 3d Division zone was wiped out. That had to be done by the 10th, for that was the day Admiral Nimitz was scheduled to arrive on a visit. There were tanks indeed and the task of finding and eliminating them was given to Major Culpepper's 2d Battalion, 3d Marines. Advancing at 0730, the battalion and a platoon of American Sherman tanks soon found two enemy mediums firing, only 400 yards up the trail the Marines were following. The Shermans left their counterparts black and burning. Seven more enemy mediums were abandoned. A Japanese infantry platoon withdrew to the coastal cliffs and was killed there.

On that day, 10 August, at 1131 as he learned that the last Japanese tanks still in action had been destroyed, General Geiger declared all organized resistance on Guam had ended. It was a great day for the Guamanians. The island was theirs again.

It was also the next to the last day for General Obata. His Mount Mataguac position was strongly defended, so much so that when the 306th had tried to force it earlier it failed. On the morning of 11 August 1944, when the general knew his headquarters had been discovered and that his enemy was coming for him, Obata signaled to his emperor:

. . . . We are continuing a desperate battle. We have only our bare hands to fight with. The holding of Guam has become hopeless. Our souls will defend the island to the very end. I am overwhelmed with sorrow for the families of the many officers and men. I pray for the prosperity of the Empire.

The 306th made the last assault supported by tanks and demolition squads. The enemy defenders killed seven Americans and wounded 17 before they went down to defeat, buried in the rubble of blown caves and emplacements. General Obata took his own life or was killed sometime during those last hours of the battle of Guam.

Major General Henry L. Larsen assumed command of the Guam Island Command at 1200, 15 August. Under him, and largely with the forces of the 3d Marine Division, the mopping up continued.

Part of Japan's terrible cost on Guam was the 10,971 bodies already counted. Yet there were some 10,000 Japanese still on the island. At first some of these men fought and staged ambushes, and a few sniped at the Americans, but soon the remaining Japanese sought only one thing—food! Most of the others fled when encountered. The Japanese now had no central command. They starved, died of dysentery, became too weak to flee, and then blew themselves up with the one precious grenade which they saved to take their own lives. Aggressive American patrols were soon killing or capturing 80 Japanese soldiers and sailors a day. A daring few stole into Marine food storage areas at night. One soldier scribbled: "All around me are enemy only. It takes a brave man indeed to go in search of food."

In addition to the battlefield casualties, more than 8,500 Japanese were killed or captured on Guam between August 1944 and the end of the war in August 1945.

In the 21 days of the Guam campaign ending 10 August, Marine units of the III Amphibious Corps reported 1,190 men killed in action, 377 dead of wounds, and 5,308 wounded. The 77th Division's casualties were 177 soldiers killed and 662 wounded. The Army and the Marines were a closely knit team in the recapture of Guam. It is reputed that General Holland Smith was the first to refer to General Bruce's troops as the "77th Marines." Major Aplington, a battalion commander in the 3d Marines, commented on the soldiers:

In their fatigues so different from our herringbone utilities and their olive drab ponchos (ours were camouflaged) so different from us . . . there was no doubt in our minds that the 77th were good people to have alongside in a fight and as a result we referred to them as "The 77th Marine Division."

On the same busy day, 10 August, only hours after Major Culpepper's battalion had knocked out the last of the Japanese tanks, the Indianapolis(CA 35) steamed into Apra Harbor with Marine Corps Commandant Lieutenant General Alexander A. Vandegrift on board, accompanying Admiral Nimitz. On 15 August, Admiral Nimitz directed that his for ward CinCPac-CinCPOA headquarters be established on Guam, and from here, he directed the rest of the Pacific War. Soon after, from airfields on Guam, as well as those on Tinian, B-29s were blasting the Japanese home islands. Hard fighting was yet to be experienced by Marine divisions on Peleliu, Iwo Jima, and Okinawa. But whether they knew it or not, the end of the war was less than a year away.

Last updated: March 14, 2024