Two atomic bombs were used against Japan before its 1945 surrender.
The United States dropped the first atomic bomb on Hiroshima on August 6, 1945. The weapon, nicknamed Little Boy, was carried by the B-29 bomber Enola Gay. A second atomic bomb, called Fat Man, was dropped on Nagasaki on August 9 by the B-29 Bockscar.
These attacks caused enormous destruction and loss of life, including deaths from injuries, burns, and radiation exposure. Their role in Japan’s decision to surrender remains part of a major historical debate. Historians also emphasize the Soviet Union’s declaration of war against Japan on August 8 and its invasion of Japanese-held territory in Manchuria.
The two bombings were the only wartime uses of nuclear weapons against cities. Japan announced acceptance of the Potsdam Declaration on August 15, and its formal surrender was signed on September 2. The Hiroshima and Nagasaki attacks therefore occurred during the final week of the Pacific War, not on the surrender date itself.