Advanced Topics
In a nutshell: World Wars reshaped nations, societies, and the global order in the 20th century.
## The World at War
The 20th century was marked by two devastating World Wars and countless regional conflicts.
### World War I (1914–1918)
- **Causes:** Nationalism, alliances, imperial tensions, and militarism.
- **Trench Warfare:** Brutal, static fighting on the Western Front.
- **Aftermath:** Collapse of empires, redrawing of borders, and the League of Nations.
### World War II (1939–1945)
- **Causes:** Treaty of Versailles, rise of fascism, expansionist policies.
- **The Holocaust:** Systematic genocide of millions.
- **Atomic Age:** Nuclear weapons changed warfare forever.
### Global Impact
- **Decolonization:** Colonies worldwide pushed for independence.
- **International Organizations:** United Nations founded to prevent future wars.
## Why This Matters
These conflicts shaped today's political boundaries, alliances, and global institutions.
Examples
- The end of World War II led to the creation of the United Nations.
- India gained independence from Britain after World War II.