Hiroshima, city on southwestern Honshū Island, Japan, capital of Hiroshima Prefecture, at the head of Hiroshima Bay. The city was founded in 1594 on six islands in the Ōta River delta. Hiroshima grew rapidly as a castle town and commercial city, and after 1868 it was developed as a military center. On August 6, 1945, during World War II (1939-1945), the first atomic bomb to be used against an enemy position was dropped on the city by the United States Army Air Forces (see Nuclear Weapons). According to U.S. estimates 60,000 ... (more)