Other Important Events

1939 - Second World War

But on Dec. 7, 1941, Japanese planes bombed the U.S. military base at Pearl Harbor, Hawaii. The United States declared war on Japan on December 8, and three days later Germany and Italy--Germany's chief ally--declared war on the United States.

An American airplane dropped the first atomic bomb used in warfare on Hiroshima, Japan, on Aug. 6, 1945. A second atomic bomb was dropped on Nagasaki on August 9. Japan formally surrendered on September 2, and the war was over.