Guam was the southern-most major island of the Marianas, 150 miles south of Saipan. Major General Roy Geiger of the III Amphibious Corps commanded the Guam operation, originally scheduled for June 1944, but delayed by the unexpected difficulty capturing Saipan. The delay gave time for more preparation bombardment and better intelligence on Guam. Naval air strikes began on 5 July. From then to 21 July planes from the Fast Carrier Task Force bombed and strafed Guam daily followed by intense shelling of coastal installations and bivouac areas immediately before the landings.
Two officers plant the American flag with a boat hook mast on Guam, eight minutes after Marines and Army units landed. 20 July 1944.
Invasion of Guam, 21 July 1944
At 0830 on 21 July 1944, 3d Marine Division hit the Asan beach while 1st Provisional Marine Brigade came ashore at Agat, seven miles apart, north and south of the main Japanese positions, harbor and airstrip on Orote Peninsula on the west side of Guam. Progress against the well-entrenched, hard-fighting Japanese defenders of the beachhead was delayed by many factors including difficult terrain, high humidity, frequent rain showers, and difficulties landing reinforcements and equipment. As on Saipan, the Japanese fired on the invading Marines from well prepared positions located in caves and tunnels as well as pillboxes situated on the beaches, cliffs, and hillsides overlooking the invasion beaches. Japanese counterattacks with infantry and tanks were repulsed by Marines on the main defensive line, with tank, carrier-plane, and naval fire support. The beachheads expanded gradually through 25 July.
Marines on Guam move up behind M4 Sherman tank, July 1944.
At 0700 on 26 July, Army artillery, backed by naval guns, planes and batteries on nearby islands, began a bombardment as cover for a new infantry assault, designed to break the defenses of Orote. Combined U.S. attacks with armor and infantry made slow progress up the peninsula, but finally completed the operation on 29 July. In four days, between 2,000 and 3,000 Japanese defenders on the Orote Peninsula had been killed as the Americans captured the territory, with its harbor and airfield.
The Japanese still held key high ground in the mountains dominating the island, and little progress had been made. The Marine and Army units from the original north and south landings linked up on 28 July and took several of the hills that threatened the beaches, creating a consolidated line for the first time. The assault phase ended with a 25-square-mile beachhead controlled by the 3d Marine Division and the 77th Division.
The pursuit phase was defined in General Geiger's order of 30 July. The 3rd Marine Division would drive up the western portion of the island while the 77th Infantry Division took eastern Guam. The 1st Provisional Marine Brigade was assigned to patrol southern Guam. This phase had major problems of transportation and movement. Because of the lack of a road across the island, the infantry had to carry everything. Men of the heavy-weapons companies labored under loads of machine guns, mortars, and ammunition.
Notwithstanding the difficulties, both the Marines and the Army units made rapid progress over the next week, fighting northward on both sides of the island. On 10 August, General Geiger announced that organized resistance on Guam had ended. The last Japanese command post was destroyed on 11 August, although stragglers were rounded up for months and a few survivors were not found until years after the end of the war.
During the invasion of Guam, US forces suffered almost eight thousand casualties, including more than one thousand killed. More than 17,500 Japanese defenders died. Thousands of native Chamorros were discovered and liberated from Japanese concentration camps.
Recommended Book about the Invasion of Guam
Find More Information on the Internet
There are many fine websites that have additional information on this
topic, too many to list here and too many to keep up with as they come and go.
Use this Google web search form to get an up to date report of what's out there.
For good results, try entering this: 1944 guam. Then click the Search button.