The Causes
| Factor | How it caused war |
|---|---|
| Division of Korea | After Japanese rule ended in 1945, Korea was divided at the 38th parallel into Soviet-occupied northern and US-occupied southern zones. This temporary division developed into two rival states. |
| Korean rivalry | Both governments claimed authority over the whole peninsula. Their competing political systems and determination to reunify Korea made peaceful coexistence unlikely. |
| Superpower rivalry | The Soviet Union supported the communist North, while the United States supported the anti-communist South. Korea therefore became part of the wider Cold War struggle between communism and containment. |
| Immediate cause | North Korea invaded South Korea in 1950, transforming political tension and border conflict into a full-scale war. |
How the War Ended
The United States intervened through a United Nations Command to defend South Korea. After UN forces advanced northward, China intervened on North Korea's side, preventing either coalition from achieving complete victory.
By the later stages of the war, fighting had reached a military stalemate near the original dividing line. An armistice in 1953 stopped active fighting and created a demilitarized zone (DMZ) separating North and South Korea. The two rival states survived, and Korea remained divided.
A common misconception is that the war ended with a peace settlement or reunification. It did neither: the armistice was only an agreement to stop fighting, so the underlying political conflict remained unresolved.
Exam Technique
For a Paper 3 essay, separate long-term causes from the immediate cause, then evaluate their relative importance. Avoid narrating the military course alone; connect Korean division and rivalry to superpower intervention, and explain why Chinese involvement produced stalemate rather than victory.
