Nagasaki was atomic-bombed on August 9, 1945, the day Soviet forces invaded Manchuria.
The United States dropped the plutonium implosion bomb known as Fat Man over Nagasaki. The bomb detonated at 11:02 a.m. local time, three days after the uranium bomb Little Boy destroyed much of Hiroshima. Nagasaki was not the first target selected for the mission, but weather and visibility affected the final approach.
The bombing occurred only hours after the Soviet Union began its offensive against Japan in Manchuria. These events followed Hirohito’s decision to accept the Potsdam Declaration, which was announced to the Japanese public on August 15. Historians continue to debate the relative importance of the atomic bombings and the Soviet entry in Japan’s surrender decision, but the chronology of the events is firmly documented.