The 1929 American stock market crash triggered a Great Depression. Western democracies expanded their powers and responded with relief programs. Authoritarian and Fascist regimes arose to replace some capitalist democracies. Only World War II ended the depression.

The radical totalitarian dictatorships of the 1920s and 1930s were repressive, profoundly antiliberal, and exceedingly violent. Mussolini set up the first Fascist government, a one-party dictatorship, but it was never truly a totalitarian state on the order of Hitler’s Germany or Stalin’s Soviet Union.

In the Soviet Union Stalin launched a socialist “revolution from above” to modernize and industrialize the U.S.S.R. Mass purges of the Communist Party in the 1930s led to the imprisonment and deaths of millions.

Hitler and the Nazi elite rallied support with a totalitarian ideology that combined racism and extreme nationalism. The Great Depression caused German voters to turn to Adolph Hitler and the Nazis for relief. After Hitler declared the Versailles treaty disarmament clause null and void, British and French leaders tried appeasement. On September 1, 1939, his unprovoked attack on Poland forced the Allies to declare war, starting World War II.

Nazi armies first seized Poland and Germany’s western neighbors and then turned east. Here Hitler planned to build a New Order based on racial imperialism. In the Holocaust that followed, millions of Jews and other “undesirables” were systematically exterminated. In Asia the Japanese created the Greater East Asian Co-Prosperity Sphere as a vehicle of Japanese domination and control. After Japan attacked Pearl Harbor, the United States entered the war. In 1945 the Grand Alliance of the United States, Britain, and the Soviet Union defeated Germany and Japan.