Overview
The Korean War was a conflict between North Korea (supported by China and the Soviet Union) and South Korea (supported by the United Nations, principally the United States). It began on June 25, 1950, when North Korean forces invaded South Korea, and fighting largely ended with an armistice on July 27, 1953.
Although an armistice was signed, no formal peace treaty was ever concluded. Technically, the two Koreas remain at war. The conflict is often called “The Forgotten War” in the United States because it was overshadowed by World War II and later by the Vietnam War.
Background & Causes
- • After Japan’s defeat in 1945, Korea was divided at the 38th parallel into two occupation zones: Soviet in the North and American in the South.
- • Two rival governments emerged: the communist Democratic People’s Republic of Korea (North) under Kim Il-sung, and the anti-communist Republic of Korea (South) under Syngman Rhee.
- • Both leaders wanted to reunify Korea under their own system. Border clashes were frequent in the late 1940s.
- • In June 1950, with Soviet approval and Chinese awareness, North Korea launched a full-scale invasion of the South.
Major Phases of the War
1. North Korean Invasion (June–September 1950)
North Korean forces rapidly overran most of South Korea. UN and South Korean troops were pushed into a small defensive perimeter around the port of Pusan (the Pusan Perimeter).
2. Inchon Landing & UN Counterattack (September–October 1950)
General Douglas MacArthur led a daring amphibious landing at Inchon. UN forces recaptured Seoul and pushed North Korean troops back across the 38th parallel, advancing deep into North Korea toward the Yalu River (border with China).
3. Chinese Intervention (October 1950–January 1951)
Hundreds of thousands of Chinese “People’s Volunteer Army” troops entered the war. UN forces were driven back south of the 38th parallel. Seoul was lost again temporarily.
4. Stalemate (1951–1953)
After heavy fighting, the front stabilized near the original 38th parallel. The war became a bloody stalemate of trench warfare, artillery duels, and limited offensives while peace talks dragged on for two years.
Key Figures
Outcome & Legacy
- • An armistice was signed on July 27, 1953. The border remained near the 38th parallel, with a Demilitarized Zone (DMZ) established.
- • No formal peace treaty has ever been signed. North and South Korea are still technically at war.
- • Casualties were extremely high: estimates of 2.5–3.5 million total dead (military and civilian), including over 36,000 American deaths.
- • The war solidified the Cold War division of Korea and demonstrated the limits of both superpowers.
- • It set important precedents for limited war and UN collective security actions.