The Battle of Peleliu, codenamed Operation Stalemate II by the United States military, was fought between the U.S. and Japan during the Mariana and Palau Campaign of World War II, from September 15 to November 27, 1944, on the island of Peleliu of the Palau archipelago in the Western Pacific.
U.S. Marines of the 1st Marine Division, and later soldiers of the U.S. Army’s 81st Infantry Division, fought to capture an airstrip on the small coral island of Peleliu. This battle was part of a larger offensive campaign known as Operation Forager, which ran from June to November 1944, in the Pacific Theater.
Major General William Rupertus, commander of the 1st Marine Division, predicted the island would be secured within four days. However, after repeated Imperial Army defeats in previous island campaigns, Japan had developed new island-defense tactics and well-crafted fortifications that allowed stiff resistance, extending the battle through more than two months. The heavily outnumbered Japanese defenders put up such stiff resistance, often fighting to the death in the Emperor’s name, that the island became known in Japanese as the “Emperor’s Island.”
The reduction of the Japanese pocket around Umurbrogol mountain has been called the most difficult fight that the U.S. military encountered in the entire war. In total, the 1st Marine Division suffered over 6,500 casualties during its month on Peleliu, over one third of the entire division. The 81st Infantry Division also suffered heavy losses with 3,300 casualties during its tenure on the island.
✯ Idahoans listed as Killed or Missing in Action, Battle of Peleliu, 15 September–27 November 1944 ✯