Nagasaki was the second Japanese city targeted by an atomic bomb during the 1945 surrender crisis.
The U.S. B-29 Bockscar dropped the plutonium bomb Fat Man on Nagasaki on August 9, 1945, three days after the uranium bomb Little Boy was dropped on Hiroshima. The attack occurred as Japan was facing the Allied ultimatum and the Soviet Union’s entry into the war.
Nagasaki was not the original primary target for the mission. Kokura was listed first, but cloud and smoke obscured the aiming point, so the aircraft proceeded to its secondary target, Nagasaki.
The bombing is often discussed together with the Soviet invasion of Manchuria and Japan’s August 15 surrender announcement. Japan formally signed its surrender on September 2. Nagasaki remains the second and, to date, last city attacked with a nuclear weapon in wartime.