The U. S. Marine Corps played a vital role in the U. S. Navy’s island-hopping campaign through the Central Pacific during World War II. Excelling at amphibious warfare, the marines overwhelmed Imperial Japanese garrisons in the Gilbert, Marshall, MARIANA, Palau, soi-omon, Bonin, and Ryukyu Islands between November 1943 and July 1945. Unlike the other and larger American combat services, the marines were largely confined to the World War II Pacific theater and saw little action in the European theater.
A constituent part of the U. S. Navy, the Marine Corps has always been the smallest of the American combat services. Traditionally serving as the navy’s land force, including providing guards at naval bases, ports, and aboard ships, the corps not only conducted amphibious operations during World War II but, unlike similar services elsewhere in the world, also had its own air force. The highest serving marine officer, the commandant of marines, had his own headquarters and staff, but he did not hold a position on the U. S. Joint Chiefs of Staff. Aboard ship, marine officers were subordinate to naval command.
Seeking an expanded combat role, the Marine Corps in 1933 created the Fleet Marine Force to undertake amphibious landings. By the time of the outbreak of World War II in 1939, about 25 percent of the corps’ 19,400 men belonged to this assault force. The Fleet Marine Force was divided into two brigades, one stationed on the East Coast at Quantico, Virginia, and the other in San Diego, California. In February 1941, the two Fleet Marine Force brigades were expanded and renamed the First and Second Marine Divisions, each consisting of three infantry regiments, an artillery regiment, and various support units. Their supporting aviation units became the First and Second Marine Aircraft Wings. Other, much smaller marine units were scattered around the globe at the time of the attack on Pearl Harbor in December 1941, in a total force numbering some 54,300 men.
Like the other military services, the U. S. Marine Corps expanded rapidly during the war. Although historically an all-volunteer force, the marines accepted draftees during
World War II in order to maintain troop levels. The corps began accepting African Americans in 1942. Between August 1943 and September 1944, the marines formed six consecutively numbered divisions that totaled some 474,680 men by V-J Day in 1945. The marines also formed raider and parachute battalions, a glider group, barrage balloon squadrons, and seven island defense battalions for guarding garrisons such as Wake Island and Guam. The marine aviation wings grew just as rapidly, from 641 pilots in 13 squadrons in December 1941, to 10,049 pilots in 128 squadrons formed into five aircraft wings, the First through Fourth and the Ninth plus a training wing. In addition, the aviation wings included 106,475 ground officers and enlisted men and women by 1945.
The First and Second Marine Divisions, and their attendant air wings, engaged in their first major operation at Guadalcanal in August 1942 as part of the combined First Marine Amphibious Corps, which became the primary amphibious operations planning headquarters in the South Pacific area. Marines also saw service elsewhere in the central and Northern Solomon Islands and at New Britain, but were always outnumbered by U. S. Army troops, the predominant force in the Pacific theater.
Before Admiral Chester W. Nimitz opened the Central Pacific offensive in November 1943, the Fifth Amphibious Corps was formed and saw service in the Gilbert Islands, landing on Tarawa on November 20, 1943, and on Eniwetok, Roi, and Namur in the Marshall Islands on February 1944. Later in 1944, both Marine Amphibious Corps came under the Fleet Marine Force, which was renamed the Fleet Marine Force, Pacific, commanded by Major General Holland M. “Howling Mad” Smith. The Second, Third, and Fourth Marine Divisions under Smith landed on Saipan, Guam, and Tinian in the Mariana Islands in June and July 1944. In October 1944, Smith relinquished his post to Major General Harry Schmidt. Following the marine assault on Peleliu in September, the marines invaded Iwo Jima in the Bonin Islands in February 1945. The bloodiest marine assault of the war, Iwo Jima cost the Third, Fourth, and Fifth Marine Divisions at least 6,000 dead and 17,000 wounded. Between April and June 1945, the First and Sixth Marine Divisions participated in the conquest of Okinawa.
U. S. Marine Corps casualties during the war amounted to 86,940, of whom 19,733 were killed, with the vast majority of casualties incurred between July 1944 and July 1945.
Further reading: Robert Leckie, Strong Men Armed: The U. S. Marines against Japan (New York: Random House, 1962); Allan Reed Millett, Semper Fidelis: The History of the United States Marine Corps (New York: Free Press, 1991).
—Clayton D. Laurie
World History
