World War II was preceded by several key events in the aftermath of WWI. The Treaty of Versailles imposed harsh penalties on Germany including war reparations that crippled its economy. This contributed to the rise of Hitler and the Nazi party in Germany. Hitler stressed nationalist ideas and promised to restore Germany's power. Japan also expanded its military influence, seizing Manchuria in 1931. Meanwhile, the US pursued isolationism and did not join the League of Nations. Under Hitler, the Nazi party took complete control of Germany and established a fascist dictatorship with Hitler as the Führer by 1933.