U.S. Involvement in WWII Timeline By sieczka.1 Dec 7, 1941 Japan bombs Pearl Harbor Feb 19, 1942 President Roosevelt orders Japanese Americans to internment camps Jun 7, 1942 U.S defeats Japan at Battle of Midway Sep 3, 1943 Allied forces invade Italy Jun 6, 1944 Invasion of Normandy Jan 26, 1945 Soviet troops liberate Auschwitz Apr 12, 1945 President Roosevelt dies, Harry Truman sworn in as President May 7, 1945 Germany surrenders Aug 9, 1945 U.S. drops atomic bombs on Hiroshima and Nagasaki, Japan Sep 2, 1945 Japan surrenders, officially ending WWII