21^st Infantry Regiment

The 21st Infantry Regiment began the war at Schofield Barracks as a Hawaiian Division regiment and became part of the 24th Infantry Division on August 26, 1941. After the Pearl Harbor attack it helped defend Oahu, then left Hawaii in July 1943 for Australia and Goodenough Island. On April 22, 1944, the regiment landed at Tanahmerah Bay in the Hollandia operation. Supply difficulties and swamp-backed beaches slowed the advance, but elements pushed inland from Depapre toward Lake Sentani, fought through the first organized resistance near Sabron, and overran Hollandia airdrome on April 26 before linking with the Humboldt Bay force.

For the Leyte invasion, the regiment was detached from the main 24th Division landing and assigned the separate mission of controlling Panaon Strait at the southeastern entrance to Leyte Gulf. After this opening phase it rejoined the division's fight in northern Leyte. In November 1944 the 21st relieved the 34th Infantry at Breakneck Ridge west of Pinamopoan. It attacked through typhoon conditions on November 8 and gained the crest on November 12, helping open the route toward the northern entrance of Ormoc Valley. Early in 1945 its companies made additional landings at Marinduque, Nasugbu Point, and Lubang.

On April 17, 1945, the regiment landed in the Malabang area on Mindanao. While the 19th moved along Route 1, the 21st advanced by engineer landing craft up the Mindanao River toward Paidu-Pulangi and Fort Pikit. In the Davao campaign it returned from reserve and fought through Mintal, Talomo River, Tugbok, and the Talomo Valley. The regiment attacked in terrain dominated by overgrown abaca plantations, river crossings, roadblocks, and hidden Japanese positions. In July, 1st Battalion joined Sarangani Task Force, landing on the north shore of Sarangani Bay on July 12 and linking with overland and guerrilla forces as organized resistance in that sector collapsed.