June-July, 1944: Battle for Saipan Summary

At 8:00 a.m. on June 15, 1944, 40,000 marines of the Second and Fourth Marine Divisions, led by Lieutenant General Holland M. Smith, began amphibious landings on beaches around Garapan, Saipan’s principal city, with the Army’s Twenty-seventh Division in reserve. The landing followed four days of bombardment from the invasion fleet, during which U.S. forces won air superiority.

Awaiting the marines were 31,650 Japanese, many of them untested and led by overconfident commanders. Despite heavy small-arms and artillery fire, both U.S. marine divisions were ashore by nightfall. They pushed through the thin beach defenses during the next day and crushed sporadic Japanese counterattacks. By the end of June 17, Japanese forces, led by Lieutenant General Yoshitsugo Saito, were in hasty retreat inland. A mass suicide attack on July 7 failed to check U.S. advances, and Saipan was declared secured on July 9, although small groups continued resistance until the end of the war. The Japanese sustained 28,500 killed in action; 3,471 Americans died, and another 13,160 were wounded.

Saipan was headquarters for the Japanese defense of the Central Pacific, a vital shield for the Japanese homeland. Its fall crippled the Japanese defense strategy and gave the Americans an airbase from which B-29 Superfortress bombers could reach Tokyo.