World War II

1939-45 (U.S. involved, 1941-46)

“I have seen war. I hate war.” —President Franklin D. Roosevelt, World War II

  • U.S. troops engaged: 16,112,566
  • American casualties: 291,557
  • The U.S. joined the Allies (Britain, France, and the USSR) to fight the Axis Powers (Germany, Italy, and Japan) after the U.S. forces were attacked by the Japanese at Pearl Harbor in 1941.
  • President Franklin Roosevelt ordered Japanese and Japanese-Americans in western U.S. to be exiled to “relocation centers,” many for the remainder of the war.
  • American troops clash with the Japanese in the Philippines and join with British troops in North Africa.
  • An invasion of Italy forces that country to surrender and join the Allies in 1943.
  • On June 4, 1944 the Allies launch the Normandy invasion on the beaches of northern France, commonly referred to as D-Day.
  • Germany surrendered in 1945, and Japan surrendered later that same year, after the U.S. dropped the atomic bomb on the cities of Hiroshima and Nagasaki.
  • One of the most horrific chapters of the war was the Holocaust, the systematic annihilation of about 6 million Jews, as well as millions of others who did not conform to Nazi Germany’s racist ideals.
  • This was the largest and most expensive war ever, as well as the most difficult to settle. The world remained politically unstable, major cities had been turned to rubble by bombings, and modern weapons combined with Germany's attempt to exterminate entire religious and ethnic groups brought death to millions of people.

See World War II for more details about the dates and events of this war.


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