Heath_WW2 Vets Day Timeline By nHeath98 Sep 1, 1939 Germany invades Poland and annexes Danzig; Britain and France give Hitler and Ultimatium May 10, 1940 Nazis invade Netherlands, Belgium, and Luxembourg (May 10). Dec 7, 1941 Japanese attacks on Pearl Harbor, Philippines, Guam force U.S. into war; U.S. Pacific fleet crippled (Dec. 7). Sep 10, 1943 Nazis seize Rome (Sept. 10). May 1, 1945 Suicide of Hitler announced (May 1). Aug 6, 1945 A-bomb dropped on Hiroshima by U.S. (Aug. 6)