Important battle in the Pacific Theater. Saipan, part of the Mariana Islands chain that includes Guam and Tinian, had become Japanese territory in 1920 as a consequence of World War I and was considered a part of Japan itself. Following the successful U.S. invasions in the Gilbert and Marshall Islands, U.S. Chief of Naval Operations Admiral Ernest J. King pushed for an assault on the Marianas. Despite opposition from General Douglas MacArthur, King's view prevailed.
The invasion force for Saipan included the 2nd and 4th Marine Divisions; the 27th Army Infantry Division was in reserve. Admiral Raymond Spruance commanded the Fifth Fleet, while Rear Admiral Richmond Kelly Turner had charge of planning and executing the landing. Marine Major General Holland ("Howlin' Mad") Smith commanded V Amphibious Corps and would be in charge of the troops once they disembarked at Saipan.
The attack plan, code-named Operation FORAGER, called for the Marines to land along a strip of beach on the western side of the island. American estimates placed up to 15,000 Japanese soldiers on Saipan, but the actual number was about 30,000 Japanese army and naval personnel. There were also many civilians. Vice Admiral Nagumo Ch?ichi, victor at Pearl Harbor and loser at Midway, commanded the Fourth Fleet, a small area fleet charged with defending the Marianas. He established his headquarters on Saipan, which was also headquarters for the Japanese Twenty-First Army, commanded by Lieutenant General Hideyoshi Obata. Lieutenant General Sait? Yoshitsugu had actual ground command on Saipan. His men were well entrenched in caves and other natural fortifications on the island, and they were well supplied with defensive firepower.
More than 800 ships transported the U.S. invasion force from Eniwetok to the Marianas. Bombardment vessels pounded Saipan for three days before the landing, but this bombardment was insufficient, as many Japanese defensive positions had not been identified. Early on the morning of 15 June, the Marines went ashore. Contrary tides and Japanese fire prevented the 2nd Marine Division, aiming for the north end of the target beaches, from landing in the preferred location. The 4th Marines landed with greater accuracy, but the Japanese mounted an excellent defense and subjected the invaders to withering artillery and mortar fire. Both the Marines and the Japanese suffered heavy casualties in the first days of the battle.
Despite stubborn Japanese opposition, the Marines slowly advanced. The 2nd Marines swung north along the western coast of Saipan, while the 4th Marines pushed across to the eastern coast of the island before they turned northward as well. On 16 and 17 June, Holland Smith committed his reserve, the 27th Infantry Division, to the battle. He deployed it between the two Marine divisions and ordered it to drive northward up the center of the island.
While the Marines and infantry were struggling to gain control of Saipan, Admiral Spruance learned that the Japanese fleet had sailed from the Philippines for the Marianas. Spruance then departed with most of his ships to engage the Japanese fleet. Vice Admiral Marc Mitscher, who commanded Task Group 58 of the American carriers, successfully defeated the Japanese threat in the 19-21 July Battle of the Philippine Sea. Known to the Americans as the "Great Marianas Turkey Shoot," this battle destroyed Japanese naval airpower, but it also deprived the Americans on Saipan of much-needed naval gunfire and air support.
In the meantime, Marines and army troops on Saipan continued to drive north. In a controversial decision, General Smith, dissatisfied with army progress, relieved Major General Ralph C. Smith from command of the 27th Infantry Division. This matter, largely the result of different tactical doctrines, led to an interservice dispute that raged well after the end of the war.
On 7 July, the Japanese mounted the largest banzai attack of the war, but that desperation charge by 3,000 Japanese soldiers was the last major effort in a lost battle. Most Japanese fought to the death rather than surrender, and their commanders committed suicide. Hundreds of Japanese civilians also leaped to their deaths from cliffs at the northern end of Saipan rather than surrender. Organized resistance on the island ended on 9 July, and Saipan was declared secure on 13 July. United States forces suffered 3,126 killed, 13,160 wounded, and 326 missing. Japanese losses were approximately 27,000 killed. Only 2,000 were taken prisoner. Nagumo and Sait? were among those who committed suicide.
The fall of Saipan brought the resignation of Japanese Premier General T?j? Hideki. Guam and Tinian in the Marianas were also secured by early August. Even as fighting for the three islands was going forward, Seabees were clearing runways for B-29 bombers to strike Japan.
Harold J. Goldberg
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