7.6 Causes of World War II

Failures of peace and rise of aggression

The Treaty of Versailles left Germany humiliated and economically crushed, fueling resentment that fascist and militarist leaders exploited. The Great Depression worsened instability worldwide, boosting extremist movements. The League of Nations proved too weak to stop aggression, failing to act against Japan's invasion of Manchuria (1931) or Italy's invasion of Ethiopia (1935).

Expansionist ideologies

Hitler's Nazi Germany pursued Lebensraum (living space) and racial empire, remilitarizing the Rhineland, annexing Austria, and seizing Czechoslovakia. Appeasement at Munich (1938) emboldened further aggression. Imperial Japan sought resource-rich territory in Asia, invading Manchuria and later China, aiming to build a Greater East Asia Co-Prosperity Sphere. Mussolini's Italy sought to revive Roman imperial glory through conquest in Africa.

Immediate triggers and alliances

The Molotov-Ribbentrop Pact (1939) between Germany and the USSR secretly divided Eastern Europe, removing fear of Soviet intervention. Germany's invasion of Poland in September 1939 triggered declarations of war from Britain and France. In Asia, ongoing Japanese expansion and the attack on Pearl Harbor (1941) drew the United States into a truly global conflict.

Key terms

Treaty of Versailles

1919 treaty that imposed harsh reparations and territorial losses on Germany, fueling resentment and nationalism.

Appeasement

Policy of conceding to aggressor demands to avoid conflict, as with the 1938 Munich Agreement over the Sudetenland.

Lebensraum

Nazi ideology calling for German territorial expansion into Eastern Europe for 'living space.'

Molotov-Ribbentrop Pact

1939 non-aggression agreement between Germany and the USSR that secretly divided Eastern Europe and enabled the invasion of Poland.

League of Nations' failure

The League failed to stop aggression like Japan's invasion of Manchuria (1931) and Italy's invasion of Ethiopia (1935), showing its weakness.

Try an AP-style question

Appeasement was the policy of…

1. giving in to Hitler's demands to avoid war
2. immediately declaring war on Germany
3. forming alliances with Japan
4. rearming France quickly