Volunteer in German Army, 1914, winning the Iron Cross. Became Leader of the National Socialist German Workers' Party (the Nazi Party) in 1921; was imprisoned for leading an uprising against the Government in 1923, but was released after just over one year. Appointed Chancellor of Germany in 1933 then Head of the German State (Führer) in 1934. Pursued an aggressive foreign policy, withdrawing from the League of Nations, then forcing Austria to declare a union (Anschluss) with Germany in March 1938. Germany then took over the German-speaking part of Czechoslovakia (the Sudetenland), after promising Britain and France in the Munich Agreement of September 1938 that this would be the last of Germany's territorial demands in Europe. Confident that the other European powers would do anything to preserve peace, Hitler then invaded Poland in 1939, triggering the Second World War. At the end of the war in 1945, Hitler committed suicide as the Soviet forces overran Berlin.