Okinawa ground order of battle

This is the order of battle for the US invasion of the island of Okinawa, the largest island of the Ryukyu chain. This offensive, called Operation Iceberg by its planners, was the final Allied offensive in the Pacific Theater of Operations in World War II.

Location of Ryukyus and beach assignments on Okinawa

Map of the Ryukyu Island chain showing its strategic location between Formosa and Kyushu, the southernmost of the Japanese Home Islands

Landing beaches on Okinawa

US ground force commanders on Okinawa

Lt. Gen. Simon B. Buckner, USA (KIA)

Maj Gen. Roy S. Geiger, USMC

Maj. Gen. John R. Hodge, USA

The defending Japanese military was determined to inflict a casualty rate so high that the U.S. government would choose not to invade the Japanese home islands. To this end, the southern portion of Okinawa had been covered with the most extensive system of fortifications and interlocking fields of fire the Americans had yet encountered in the Pacific Theatre. In anticipation of this level of resistance, five full divisions, two Marine and three Army, were committed to the struggle.

The initial American landings took place on 1 April 1945 and the island was not declared secure until 22 June, a period of 82 days, far longer than was expected by US planners. Four days before the end of the campaign, Lieutenant General Simon Bolivar Buckner Jr. became the highest ranking U.S. military officer to be killed in action in the Second World War.