Korean War
The Korean War was fought between North Korea and South Korea from 1950 to 1953. The war began on 25 June 1950 when North Korea invaded South Korea following clashes along the border and rebellions in South Korea. North Korea was supported by China and the Soviet Union while South Korea was supported by the United States and allied countries.
After the first two months of war, South Korean Army (ROKA) and American forces hastily dispatched to Korea were on the point of defeat, retreating to a small area behind a defensive line known as the Pusan Perimeter. In September 1950, a risky amphibious UN counteroffensive was launched at Incheon, cutting off Korean People's Army (KPA) troops and supply lines in South Korea. Those who escaped envelopment and capture were forced back north. UN forces invaded North Korea in October 1950 and moved rapidly towards the Yalu River—the border with China—but on 19 October 1950, Chinese forces of the People's Volunteer Army (PVA) crossed the Yalu and entered the war. The UN retreated from North Korea after the First Phase Offensive and the Second Phase Offensive. Chinese forces were in South Korea by late December.
In these and subsequent battles, Seoul was captured four times, and communist forces were pushed back to positions around the 38th parallel, close to where the war had started. After this, the front stabilized, and the last two years were a war of attrition. The war in the air, however, was never a stalemate. North Korea was subject to a massive US bombing campaign. Jet-powered fighters confronted each other in air-to-air combat for the first time in history, and Soviet pilots covertly flew in defense of their communist allies.
The fighting ended on 27 July 1953 when the Korean Armistice Agreement was signed. The agreement created the Korean Demilitarized Zone (DMZ) to separate North and South Korea, and allowed the return of prisoners. However, no peace treaty was ever signed, and the two Koreas are technically still at war, engaged in a frozen conflict.
The Korean War was among the most destructive conflicts of the modern era, with approximately 3 million war fatalities and a larger proportional civilian death toll than World War II or the Vietnam War. It incurred the destruction of virtually all of Korea's major cities, thousands of massacres by both sides, including the mass killing of tens of thousands of suspected communists by the South Korean government, and the torture and starvation of prisoners of war by the North Koreans. North Korea became among the most heavily bombed countries in history.