Saipan, Marianas, Central Pacific · July 6, 1944

The Battle of the Philippine Sea (June 19–20, 1944) was a pivotal U.S. naval victory, effec­tively elim­i­nating Japan’s ability to both con­duct large-scale carrier actions and rein­force its gar­ri­sons to the east in the Mari­anas. The most impor­tant islands in the Mari­ana chain were Guam (an Amer­i­can ter­ritory cap­tured by Japan on Decem­ber 8, 1941), Tinian, and Saipan (two Japanese World War I mandates).

Amphibious U.S. Marine and Army divisions had landed on Sai­pan begin­ning June 15. On this night in 1944 on Sai­pan, three thou­sand Japa­nese troops—real­izing that they could not defeat the in­vaders—hurled them­selves against Amer­i­can lines in the largest ban­zai charge of the war. Led by Japa­nese offi­cers swinging swords over­head, the sui­cidal charge of able-bodied men in the front ranks, the lame and wounded in the rear, some armed only with rocks or knives mounted on sticks, left most Japa­nese attackers dead and battle-hardened Marines and soldiers shaken to the core.

The self-inflicted slaugh­ter was not over. The next day brought another suicidal ban­zai charge and mass sui­cides, in­cluding that of Emperor Hiro­hito’s hero at Pearl Harbor and Mid­way, Vice Admiral Chūi­chi Na­gu­mo. Two U.S. Army regi­ments were almost de­stroyed, losing 650 killed and wounded in this last-ditch charge on July 7. Hund­reds of Japa­nese civil­ians jumped off cliffs, drowned them­selves, or blew them­selves up with gre­nades. All told, 29,000 Japa­nese mili­tary and 22,000 civil­ians (half the popu­la­tion of the island) died ver­sus 3,426 Amer­i­can dead and 10,364 wounded, making Sai­pan the most costly victory to date in the Pacific War.

News that Sai­pan had been lost caused Japa­nese Pre­mier Hideki Tōjō and his cabi­net to resign later in the month. Until Sai­pan’s capture the Japa­nese popu­lace con­tin­ued to believe that suc­cess in the war remained pos­sible. Now Japan’s leader­ship was forced to begin con­sidering the reality of defeat. Marine General Hol­land M. “Howlin’ Mad” Smith, ground com­man­der of the assault on Sai­pan, declared that the U.S. victory “opened the way to the home islands” by pro­vid­ing secure air bases for the new long-range heavy bombers that were now within striking dis­tance of all Japa­nese cities. Four months later one hun­dred B‑29 Super­for­tresses departed Sai­pan’s new U.S. air­strips for their first massive air raid over Tokyo.

Saipan and Tinian, 1944–1945. U.S. Begins End Game for Pacific War

Marines, Red Beach, Saipan, June 16, 1944U.S. Army 27th Infantry Division, Saipan, June 1944

Left: U.S. Marines take cover on Red Beach, June 15, 1944. The inva­sion fleet of hun­dreds of ships carried more than 70,000 Marines and sol­diers. Shelling the pistol-shaped island began on June 11, 1944, and lasted for more than three days. Landings began on the west side on June 15 when the 2nd Marine Divi­sion hit Red and Green beaches and the 4th Marine Division hit Blue and Yellow beaches.

Right: Soldiers of the U.S. Army 27th Infantry Divi­sion, green rein­force­ments, dis­em­bark from LSTs and pro­ceed across a coral reef on the extreme southwest coast of the Saipan. Photo from June 16 or 17, 1944.

Marines and M4 Sherman, Saipan, July 8, 1944Marine with pistol, Saipan 1944

Left: Marines take cover behind an M4 Sher­man tank while clearing out the northern end of Saipan Island, July 8, 1944.

Right: Holding a Colt 45 pistol, a Marine moves cau­tiously through the Sai­pan jungle, July 1944, as he and his pla­toon fer­ret out the enemy. Out of a 30,000-strong garri­son, less than 1,000 Japa­nese were taken pri­soner. The sui­cides and ban­zai charges were called gyokusai, which can be roughly trans­lated as “breaking the jewel,” a refer­ence to the destruc­tion of an entire Japa­nese unit. Gyokusai can only be made at the behest of Imperial General Headquarters.

Marine and Chamorro family, June 1944Isley Field on Saipan, mid-1945

Left: Marine Lt. Robert B. Sheeks, an Intelli­gence and Japa­nese Lan­guage Offi­cer, coaxes a ter­ri­fied island native (a Cha­morro woman) and her chil­dren into aban­doning their hiding place, circa June 21, 1944. Using a com­bina­tion of sur­render leaf­lets and ampli­fied voice appeals, Sheeks per­son­ally ended up saving the lives of hun­dreds of Japa­nese civil­ians and service­men by being able to talk them out of the many caves in Sai­pan’s and Tinian’s volcanic landscape during combat in 1944.

Right: Isley Field on Saipan is filled with B‑29 Super­for­tresses in this mid‑1945 photo. The Mari­anas were desired by the U.S. as bomber bases to reach the Japa­nese main­land, with Sai­pan attacked for that reas­on even before the U.S. moved to reca­pture Guam. Once cap­tured, Sai­pan and Tinian were used by the U.S. Twen­tieth Air Force because the islands finally put main­land Japan within round-trip range of B‑29s. In response, Japa­nese air­craft attacked the bases on Sai­pan and Tinian from Novem­ber 1944 to Janu­ary 1945. Both the Enola Gay and the Bocks­car (which dropped atomic bombs on Hiro­shima and Naga­saki, respec­tively) flew their missions from Tinian’s “North Field.”

The Invasion of Saipan, June 1944: Piercing Japan’s Pacific Defensive Perimeter