Modern World History
The 20th century was the most transformative in human history — two world wars, the atomic age, decolonization, the Cold War, and the rise of globalization reshaped every nation on Earth.
World War I (1914–1918)
WWI was triggered by the assassination of Archduke Franz Ferdinand but caused by deeper tensions: militarism, alliances, imperialism, and nationalism (MAIN).
| Allied Powers | Central Powers |
|---|---|
| Britain, France, Russia, later USA | Germany, Austria-Hungary, Ottoman Empire |
Key features: trench warfare, poison gas, machine guns, tanks. ~20 million dead. The Treaty of Versailles (1919) blamed Germany, imposed harsh reparations, and set conditions for WWII.
World War II (1939–1945)
WWI's aftermath — economic depression, political instability, and the rise of fascism — led to WWII.
- Axis Powers: Germany (Hitler), Italy (Mussolini), Japan
- Allied Powers: UK, France, USSR, USA (after Pearl Harbor, 1941)
- Holocaust: Nazi Germany systematically murdered 6 million Jews and millions of others
- D-Day (June 6, 1944): Allied invasion of Normandy turned the tide in Europe
- Atomic bombs on Hiroshima and Nagasaki (August 1945) ended the Pacific war
~70–85 million dead — the deadliest conflict in human history.
The Cold War (1947–1991)
After WWII, two superpowers — the USA (capitalism/democracy) and USSR (communism) — competed globally without direct military conflict.
| Event | Year | Significance |
|---|---|---|
| Berlin Wall built | 1961 | Divided communist East from democratic West Germany |
| Cuban Missile Crisis | 1962 | Closest the world came to nuclear war |
| Moon Landing | 1969 | USA wins the "Space Race" |
| Berlin Wall falls | 1989 | Symbolized collapse of communism in Eastern Europe |
| USSR dissolves | 1991 | Cold War ends; 15 new nations form |
Quick Quiz
Test what you just learned. Choose the best answer for each question.