Hiroshima was the first Japanese city struck by an atomic bomb, on August 6, 1945.
The United States dropped the uranium-235 bomb code-named “Little Boy” from the B-29 bomber Enola Gay at about 8:15 a.m. local time. Hiroshima was selected as the primary target during the final stages of World War II, with Kokura and Nagasaki designated as alternatives if weather or other conditions prevented the attack.
The bombing caused catastrophic destruction and loss of life. Tens of thousands of people died immediately or soon afterward, while many more later suffered injuries and radiation-related illness. The exact death toll remains difficult to establish because people were vaporized, records were destroyed, and many victims died in the following months and years.
Nagasaki was hit three days later, on August 9, by a different weapon, the plutonium bomb “Fat Man.” Hiroshima therefore comes first chronologically; Nagasaki was the second city bombed. Japan announced its surrender on August 15, and World War II formally ended in September 1945.