Key takeaways
- The Office of the Historian says the US and USSR agreed during the Second World War to divide Korea temporarily at the 38th parallel to oversee the removal of Japanese forces.
- Wikipedia dates the war from North Korea's invasion on 25 June 1950 to the armistice of 27 July 1953.
- After the Inchon landing of 15 September 1950 pushed UN forces north, Chinese troops crossed the Yalu on 19 October 1950.
- The National Archives calls the armistice talks the longest negotiated armistice in history: 158 meetings over two years and 17 days.
- Wikipedia gives around one million military deaths and an estimated 1.5 to 3 million civilian deaths; no peace treaty has been signed.
The Korean War began on 25 June 1950, when North Korea invaded South Korea, and the fighting ended with an armistice on 27 July 1953 that left the peninsula divided roughly where it had been at the start. The National Archives sums up the outcome bluntly: North and South Korea "remain separate and occupy almost the same territory they had when the war began." No peace treaty has ever been signed.
Wikipedia gives the cost as around one million military deaths and an estimated 1.5 to 3 million civilian deaths — a range wide enough that it should be quoted as a range.
A temporary line that became a border
Korea had been a Japanese colony for 35 years, Wikipedia notes. The Office of the Historian explains the division: during the Second World War, the United States and the Soviet Union agreed to divide Korea temporarily at the 38th parallel to oversee the removal of Japanese forces. Separate governments formed in 1948 — Kim Il Sung's in Pyongyang, backed by the Soviets, and Syngman Rhee's in Seoul, backed by the Americans — and each claimed to be the legitimate government of all Korea. Wikipedia describes extensive border clashes, and Rhee's government suppressing communist uprisings at Jeju and Yeosu-Suncheon. The much older history of the peninsula is in Korean dynasties explained.
The Office of the Historian adds a cause rooted in American signals. The United States, it says, did not make Korea a key part of its East Asian defence strategy and withdrew its forces from the south in the late 1940s. "Assuming that the United States did not consider South Korea of vital interest, Kim's army attacked the South in June 1950."
1950: invasion, Inchon and the Yalu
The first year swung from one end of the peninsula to the other:
| Date | Event |
|---|---|
| 25 June 1950 | North Korea invades; the UN Security Council, in the Soviet representative's absence, calls on members to help repel it |
| 27 June | Truman orders US air and sea forces to aid South Korea |
| 28 June | Seoul falls |
| Early August | UN and South Korean forces hold only the Pusan Perimeter in the south-east |
| 15 September | UN forces land at Inchon near Seoul, cutting North Korean supply lines |
| October | UN forces cross into North Korea and take Pyongyang |
| 19 October | Chinese People's Volunteer Army crosses the Yalu |
| December | UN forces retreat from North Korea |
Wikipedia notes that the UN command drew on 21 countries, with the United States providing around 90% of the military personnel, and that Truman called it a "police action" because the US never formally declared war. The People's Republic of China had been proclaimed less than a year earlier, as described in China's revolutions of 1911 and 1949.
1951–1953: stalemate and the longest truce talks
Communist forces retook Seoul in January 1951 and lost it again two months later. On 11 April 1951 Truman relieved General Douglas MacArthur; among the reasons Wikipedia lists are that MacArthur had crossed the 38th parallel in the mistaken belief that China would not intervene, and that he believed the use of nuclear weapons should be his decision rather than the president's. By mid-1951 the front had settled roughly along the 38th parallel.
Armistice talks began in July 1951, first at Kaesong and then at Panmunjom, while the fighting became a war of attrition. Wikipedia describes UN bombing that destroyed virtually all of North Korea's major cities. The hardest issue was prisoners: many Chinese and North Korean prisoners refused to be repatriated, which their governments would not accept. A way through came from India: its proposal, adopted by the UN General Assembly on 3 December 1952 as Resolution 610, created a Neutral Nations Repatriation Commission.
The National Archives calls it "the longest negotiated armistice in history: 158 meetings spread over two years and 17 days." Counting back two years and 17 days from 27 July 1953 gives 10 July 1951, the date Wikipedia gives for the opening of talks at Kaesong — 748 days in all, or one meeting roughly every 4.7 days.
What the armistice did, and did not, do
At 10 a.m. on 27 July 1953, the National Archives records, Lt. Gen. William K. Harrison, Jr., for the UN Command, and Gen. Nam Il, for the North Korean and Chinese forces, signed 18 copies of the agreement in three languages at Panmunjom, "scarcely acknowledging each other." The truce took effect at 10 p.m. It withdrew forces from a 4,000-metre-wide Demilitarized Zone and set up a Military Armistice Commission to handle violations.
The National Archives stresses that the agreement is "purely a military document — no nation is a signatory." Wikipedia adds that South Korea's president refused to sign, and describes the Korean conflict as frozen rather than finished, with flare-ups such as the 1966–1969 DMZ Conflict. The Office of the Historian notes that in 1953 the United States and South Korea signed a mutual security treaty — and that the war turned Korea "from a peripheral region to a key battle ground in the Cold War," the wider rivalry traced in the Cold War explained.
On the casualty figures, the same caution applies as for the Second World War death toll: Wikipedia's "around one million" military and "1.5 million to 3 million" civilian deaths are estimates, and the civilian range spans a factor of two.
World History Timeline Sim, our app, lets you browse 1945–1953 by year and region, and its map shows where major events happened. Its Time Travel Mode explores what-if choices whose consequences are simulated, not historical, and the app is a companion to coursework rather than a replacement. More guides are in education and brain training.
Good to know
Frequently asked questions
Why was Korea divided at the 38th parallel?
Why did China enter the Korean War?
Who signed the Korean Armistice Agreement?
Is the Korean War still officially going on?
Sources
- The Korean War, 1950–1953 (opens in a new tab)Office of the Historian, US Department of State — accessed
- Armistice Agreement for the Restoration of the South Korean State (1953) (opens in a new tab)National Archives (US) — accessed
- Korean War (opens in a new tab)Wikipedia — accessed
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