Unit 9 By madisonm Jan 1, 1934 MaoZedong heads Long March Jan 1, 1939 Germany invades Poland; France and Great Britain declare war on Germany Jan 1, 1941 Japan attacks Pearl Harbor Jan 1, 1945 United Nations formed May 1, 1945 Germany surrenders Aug 31, 1945 Allies use atomic bombs on Hiroshima and Nagasaki