Hitler took advantage of Britain and France's appeasement policies to aggressively expand German territory. Between 1936-1939, Germany annexed the Rhineland, Austria, the Sudetenland region of Czechoslovakia, and invaded the rest of Czechoslovakia. In 1939, Germany signed a non-aggression pact with the Soviet Union to divide Poland between them, and invaded Poland from the west while the Soviets invaded from the east, marking the start of World War II. Germany then launched surprise Blitzkrieg attacks to quickly conquer Norway, Denmark, the Netherlands, Belgium, Luxembourg and France by June 1940.