WW II was beginning in Europe at the 1. Sept. 1939 and was ending at the 8. May 1945.
The start of the war is generally held to be September 1, 1939 with the German invasion of Poland, although Britain and France entered two days later. Other dates for the beginning of war include the Japanese invasion of Manchuria on September 13, 1931, the start of the Second Sino-Japanese War on July 7, 1937, or one of several other events. Other sources follow A. J. P. Taylor, who holds that there was a simultaneous Sino-Japanese War in East Asia, and a Second European War in Europe and her colonies, but they did not become a World War until they merged in 1941; at which point the war continued until 1945. This article uses the conventional dating.
The end of the War also has several dates. Some sources state that it ended at the armistice of August 14, 1945, rather than the formal surrender of Japan (September 2, 1945); in some European histories, it ended on V-E Day (May 8, 1945). The Treaty of Peace with Japan was not signed until 1951