Nagasaki was hit by the second atomic bomb in August 1945, three days after Hiroshima.
The United States dropped the plutonium implosion weapon Fat Man on Nagasaki on August 9, 1945. The first atomic bomb, Little Boy, had been dropped on Hiroshima on August 6. Nagasaki was selected after weather and operational conditions affected the mission's targeting decisions.
The bomb exploded over the Urakami Valley, an industrial area northwest of central Nagasaki. The city's hills and uneven terrain affected the blast pattern, but the attack still caused enormous destruction and loss of life. Nagasaki had shipyards, factories, and other wartime industries, including facilities operated by Mitsubishi.
The bombing occurred on the same day that the Soviet Union declared war on Japan and invaded Japanese-held territory in Manchuria. Japan announced its decision to surrender six days later, although historians continue to debate the relative importance of the atomic bombings, Soviet entry, and Japan's internal political crisis.