World War II (1939–1945)

Causes

World War II resulted from:

• The failure of the League of Nations and the post-World War I settlement
• The rise of fascism in Germany, Italy, and Japan
• Economic depression and political instability
• The policy of appeasement that encouraged Adolf Hitler's aggression
• Hitler's ideology of racial supremacy and Lebensraum (living space for Germany)

The Course of the War

Germany invaded Poland on September 1, 1939, triggering the war. The war eventually involved almost every country in the world, divided into:

The Allies: Britain, France, Soviet Union, United States, China
The Axis Powers: Germany, Italy, Japan

The war ended in 1945 with the defeat of Germany (May 1945) and Japan (August 1945, after the United States dropped atomic bombs on Hiroshima and Nagasaki).

Consequences of WWII

World War II was the deadliest conflict in human history, killing approximately 70–85 million people, including 6 million Jews murdered in the The Holocaust.

Key consequences:

• The United States and Soviet Union emerged as the two superpowers
• Europe was devastated and lost its dominant position in world affairs
• The United Nations was created in 1945 to replace the failed League of Nations
• Decolonization accelerated — Asian and African countries began gaining independence
• The Cold War began between the USA and USSR