In 1933, Hitler announced that Germany would rearm itself in violation of the Treaty of Versailles. His first alliance was the Rome-Berlin Axis with Italy in 1936. This brought the two fascist states together. The Anti-Comintern Pact in 1937 saw Germany and Japan pledge to stop the spread of communism. Hitler annexed Austria in 1938 despite protests. He then invaded the Sudetenland with the appeasement of Britain, France, and Italy at the Munich Conference. Germany and the Soviet Union shocked the world with their non-aggression pact in 1939 before Germany invaded Poland, starting World War II.