Hiroshima was the first Japanese city targeted by an atomic bomb before Japan announced its surrender.
The United States dropped the uranium atomic bomb Little Boy on Hiroshima on August 6, 1945. The explosion devastated much of the city and caused enormous loss of life, including deaths from injuries and radiation effects. Hiroshima was a major military and industrial center, but the bombing also killed large numbers of civilians.
Three days later, on August 9, the United States dropped the plutonium bomb Fat Man on Nagasaki. On that same date, the Soviet Union began its offensive against Japanese forces in Manchuria. Japan's leaders faced these developments while debating whether to accept the Allied terms, and Emperor Hirohito ultimately supported surrender.
Hiroshima is sometimes confused with Nagasaki because both bombings immediately preceded the surrender announcement. Hiroshima was first; Nagasaki was second. Hirohito's recorded announcement reached the Japanese public on August 15, and the formal surrender document was signed on September 2.