Operations Located some 3,300 miles west of Hawaii and 1,400 miles east of the Philippines, the Marianas archipelago consists of fifteen volcanic islands. The Marianas already had a long history of foreign domination before the Japanese arrived to incorporate the archipelago and its Chamorro people into a new imperial order. First held by the Spanish since the late seventeenth century, then, except for Guam, passed to the Germans in 1899, the islands were taken by the Japanese during World War I, an occupation ratified by the Treaty of Versailles. Even before they left the League of Nations in 1935, the Japanese had begun fortifying the Marianas. By the 1940s the islands stood as a keystone in the defensive line around the Japanese Empire. The Imperial Japanese Navy exercised theater control over the Marianas and surrounding seas through its Central Pacific Area Fleet, commanded by Vice Adm. Chuichi Nagumo, leader of the Pearl Harbor strike force. The Imperial Japanese Army controlled all ground forces in the Marianas through its 31st Army, commanded by Lt. Gen. Hideyoshi Obata. Major subordinate commands were the 43d Division on Saipan and the 29th Division on Guam. Although both units were understrength, having lost several troop transports to American submarines, both were also augmented by a number of independent battalions and naval landing units. Japanese forces in the Marianas, both Imperial Army and Navy, totaled about 59,000 men. The Marianas campaign expanded United States Army operations in a theater commanded by the U.S. Navy. Admiral Nimitz assigned overall campaign responsibility to Vice Adm. Raymond A. Spruance's Fifth Fleet. Vice Adm. Richmond Kelly Turner would command the Joint Expeditionary Force charged with the amphibious assault. Turner himself would also command directly a Northern Attack Force against Saipan and Tinian, while a Southern Attack Force under Rear Adm. Richard L. Conolly would assault Guam. Vice Adm. Marc A. Mitscher's Fast Carrier Task Force and Vice Adm. Charles A. Lockwood's Submarine Force, Pacific Fleet, would cover all landings. Lt. Gen. Holland M. Smith, USMC, Commanding General, V Amphibious Corps, would control the Marianas amphibious forces as each left U.S. Navy control at the water's edge. Three Marine Corps general officers would command the landing forces on the targeted islands: Holland Smith on Saipan, Harry Schmidt on Tinian, and Roy S. Geiger on Guam. Amphibious units assigned to the Marianas included the 2d' 3d' and 4th Marine Divisions and a separate Marine brigade. Three major Army units—the 27th and 77th Infantry Divisions and XXIV Corps Artillery—were assigned from U.S. Army Forces in the Central Pacific Area, commanded by Lt. Gen. Robert C. Richardson, Jr. Army and Marine Corps units totaled 106,000 men. Naval support for this huge force included 110 transport vessels and auxiliaries and 88 fire support ships, from rocket gunboats to aircraft carriers. Southern Marianas 1944 (map) Continued Western Pacific, Page 3 Copyright 2006 nopukob.com