Battle of Saipan
The Battle of Saipan was a significant military engagement during World War II, taking place from June 15 to July 9, 1944. U.S. Marines, numbering around 40,000, launched an amphibious assault on the island, supported by the Army's Twenty-seventh Division and extensive naval bombardment aimed at securing air superiority. The Japanese defenders, approximately 31,650 strong under Lieutenant General Yoshitsugo Saito, faced challenges due to overconfidence and inexperience, leading to their rapid retreat inland after initial U.S. landings. Despite fierce fighting and heavy casualties on both sides—28,500 Japanese and 3,471 Americans killed—the U.S. forces ultimately secured Saipan, which held strategic importance as a base for future operations in the Pacific. The loss of Saipan severely weakened Japanese defense capabilities and allowed American B-29 bombers to launch attacks directly on the Japanese homeland. This battle not only marked a turning point in the Pacific theater but also had long-lasting implications for the course of the war.
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Subject Terms
Battle of Saipan
Type of action: Amphibious assault in World War II
Date: June 15-July 9, 1944
Location: Saipan, one of the Mariana Islands in the Central Pacific
Combatants: 66,779 Americans vs. 31,650 Japanese
Principal commanders:American, Lieutenant General Holland M. Smith (1882–1967); Japanese, Lieutenant General Yoshitsugo Saito
Result: U.S. capture of the island
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.
Significance
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.
Bibliography
Alexander, Joseph H. A Fellowship of Honor: The Battle History of the United States Marines. New York: HarperCollins, 1997.
Denfeld, D. Colt. Hold the Marianas: The Japanese Defense of the Mariana Islands. Shippensburg, Pa.: White Mane, 1997.
Lorelli, John A. To Foreign Shores: U.S. Amphibious Operations in World War II. Annapolis, Md.: Naval Institute, 1995.