World War II By pweberplp Sep 1, 1931 Japan Seizes Manchuria Feb 1, 1933 Japan Withdraws from League of Nations Oct 1, 1933 Hitler Pulls Germany out of the League of Nations Jan 1, 1934 Hitler secretly builds up army and weapons Jan 1, 1936 Hitler enters Rhiland Mar 1, 1936 Hitler makes a pact with Italy and Japan Jul 1, 1937 Japan continues to expand into China Mar 1, 1938 Hitler marches into Austria Mar 1, 1939 Hitler invades Sudetenland, Czechoslovakia Sep 1, 1939 Germany invades Poland Sep 3, 1939 Great Britain and France declare war on Germany Dec 7, 1941 Japan attacks Pearl Harbor Dec 8, 1941 U.S. Declares war on Japan entering WWII