10 Events of the European Theater By ldavis6 Sep 1, 1939 Germany invades Poland Sep 3, 1939 Great Britain and France declare war on Germany Apr 9, 1940 Germany invades Denmark and Norway Period: Jul 1, 1940 to Oct 1, 1940 Battle of Britain Apr 6, 1941 Germany invades Greece and Yugoslavia Jun 22, 1941 Germany invades the Soviet Union Dec 11, 1941 Germany and Italy declare war on the U.S. Period: Aug 1, 1942 to Feb 1, 1943 Battle of Stalingrad (turning point of the war) Jun 1, 1944 Allies invade Normandy (D-Day) May 7, 1945 Germany surrenders and WWII ends