Okinawa, Battle of (1945).Landing day for Okinawa, the final land battle of the Pacific War, was Easter Sunday, 1 April 1945. The Landing force was the new Tenth Army under Army Lt. Gen. Simon Bolivar Buckner. He commanded two corps, XXIV Corps, with five army divisions, and III Amphibious Corps, with three Marine divisions, all told some 182,000 troops. In overall charge was Vice Adm. Raymond A. Spruance, commander of the Fifth Fleet.

Okinawa, sixty miles long and from two to twenty‐eight miles wide, is the largest and most important of the Ryukyu Islands. The 500,000 Okinawans were not then considered to be Japanese.

Japanese Lt. Gen. Mitsuru Ushijima commanded the Thirty‐second Army, strength of 77,000 troops, who with naval forces and some 20,000 Okinawan conscripts provided about 100,000 defenders. Ushijima planned a defense in depth, with his main strength in the heavily populated south, and three major defense lines following east‐west ridgelines.

Buckner landed his two corps, each with two divisions in the assault, across surprisingly undefended beaches near Hagushi village on the western side of the narrow waist of the island. The III Corps on the left and XXIV Corps on the right crossed the island almost without enemy contact. The Marines then turned northward and the army headed south. On 6 April, XXIV Corps ran into the outer rings of Ushijima's first major defense line running along Kakazu ridge.

Ushijima's plan was to delay his counterattack until much of the supporting U.S. invasion fleet of some 1,200 ships was crippled by massive combined sea and air action, including suicide kamikaze tactics. The first major kamikaze attack came on 6 April. Joining the air action, the giant 18‐inch‐gun battleship Yamato sortied from the home islands, but was destroyed by U.S. Navy aircraft. Ashore, Ushijima's companion counterattack, not launched until 12 April, was easily absorbed by XXIV Corps. Meanwhile, III Corps had overrun most of central and northern Okinawa. Buckner, to overcome Ushijima's stiffening resistance, began shifting the III Corps to the south.

Ushijima's second major counterattack, timed to coincide with the fifth kamikaze attack, went off piecemeal on 3 May and accomplished nothing.

Buckner went forward with a two‐corps attack on 11 May. Ushijima's second line, which passed through Shuri, was broken on both of his flanks. He elected to fall back to his third and final line on the southern tip of Okinawa.

Buckner launched his final large‐scale attack on 18 June. The general was killed by a Japanese shell while watching the action from a forward observation post. Command of Tenth Army passed to Marine Maj. Gen. Roy S. Geiger of III Corps, who declared the island “secured” on 21 June. That same day, Ushijima committed ceremonial suicide. The last of the ten major air attacks came on 22 April. Next day, Gen. Joseph Stilwell arrived and took command.

Although liked by his subordinates, army and Marine, Buckner was considered an inexperienced commander. He was criticized by, among others, Administrative Spruance and Gen. Douglas MacArthur for his unimaginative and costly frontal assaults and his refusal to try a second amphibious landing on the southern end of the island, which might have broken the stalemate. Tenth Army casualties were 7,613 killed or missing in action and 31,800 wounded. Close to 5,000 U.S. sailors died and as many more were wounded. Seven U.S. carriers had been badly damaged and many other smaller ships were sunk or damaged. Estimates of Japanese casualties ran over 142,000, including many hapless Okinawan civilians.
[See also Marine Corps, U.S.: 1914–45; World War II: U.S. Naval Operations in: The Pacific.]

Bibliography

Roy E. Appleman, et al. , Okinawa: The Last Battle, 1948.
Samuel Eliot Morison , Victory in the Pacific, 1960.
Benis M. Frank and and Henry I
Shaw, Jr. , History of U.S. Marine Corps Operations in World War II: Victory and Occupation, 1968.
Hiromichi Yahara , The Battle for Okinawa, 1997.

Edwin Howard Simmons