William Walsh was a United States Marine who heroically sacrificed his life to save the lives of his fellow Marines during the Battle of Iwo Jima during World War II. Walsh at Iwo Jima, while leading his men against a fortified hill on February 27, 1945, threw himself on a hand grenade, sacrificing his life to save the lives of fellow Marines. For this heroic act, he was posthumously awarded the Medal of Honor. Initially buried in the 5th Marine Division Cemetery on Iwo Jima, GySgt Walsh's remains were later reinterred in Arlington National Cemetery on April 20, 1948. For his actions on February 27, 1945, he posthumously received the Medal of Honor.