Timeline By Alethea Rebenson Jul 7, 1937 Japanese invasion of China the Japanese had to crush the foundation upon which the Communists existed: when the Kwantung Army of the Empire of Japan invaded Manchuria immediately following the Mukden Incident. Sep 5, 1939 German Blitzkrieg Sep 7, 1939 Germany's invasion of Poland Jun 22, 1941 Operation Barbarossa Dec 7, 1941 Pearl Harbor Jan 20, 1942 Wannsee Conference Jul 24, 1943 Operation Gomorrah Jun 6, 1944 D-Day Dec 16, 1944 Battle of the Bulge Feb 13, 1945 Operation Thunderclap Feb 19, 1945 Battle of Iwo Jima Apr 1, 1945 Battle of Okinawa May 8, 1945 VE Day Aug 6, 1945 Dropping of the atomic bombs Sep 2, 1945 VJ Day