---
title: "Korean War Begins"
year: 1950
country: "South Korea"
canonical: "https://recap.at/1950/korean-war"
slug: "korean-war"
recapType: "global_event"
startDate: "1950-06-25"
---

# Korean War Begins

> North Korea's invasion of the South triggered the first Cold War proxy conflict and divided the peninsula for over 70 years.

On June 25, 1950, North Korea invaded South Korea, triggering a three-year war that killed millions and divided the peninsula into two separate states. The conflict pitted communist forces backed by the Soviet Union and China against South Korea and a United Nations-led force dominated by the United States, establishing a military stalemate that persists today.

## Summary

The Korean War was an armed conflict fought on the Korean Peninsula between North Korea and South Korea and their allies. North Korea was supported by China and the Soviet Union, while South Korea was supported by the United Nations led by the United States under the auspices of the United Nations Command (UNC). The conflict was one of the first major proxy wars of the Cold War and one of its deadliest conflicts on noncombatants, as it is estimated that 1.5 to 3 million civilians were killed during the war. The war was the first time the United Nations Security Council authorized the use of force under Chapter VII of the United Nations Charter.

## Key facts

- **Invasion date**: June 25, 1950
- **North Korean forces at invasion**: approximately 90,000 troops
- **UN authorized involvement**: June 27, 1950
- **U.S. Commander**: General Douglas MacArthur
- **Armistice signed**: July 27, 1953
- **War deaths (estimated)**: 2–3 million combatants and civilians
- **Final demarcation line**: near original 38th parallel
- **UN Security Council voting**: Soviet Union absent, allowing authorization

## Timeline

- **1950-06-25** - North Korea invades South Korea
  North Korean forces cross the 38th parallel in a coordinated military offensive, capturing Seoul within days and pushing South Korean forces south.
- **1950-06-27** - UN Security Council authorizes military intervention
  With the Soviet Union absent from the council, the U.S. secures authorization for UN-led military action. President Truman orders American forces to support South Korea.
- **1950-07-08** - General MacArthur assumes command of UNC
  General Douglas MacArthur is appointed commander of the United Nations Command, consolidating American and allied forces under a single authority.
- **1950-09-15** - Inchon Landing
  MacArthur executes an amphibious landing behind North Korean lines at Inchon, rapidly reversing the military situation and forcing North Korean forces northward.
- **1950-10-19** - UN forces enter North Korea
  UN and South Korean troops cross the 38th parallel and push toward the Yalu River, approaching the Chinese border.
- **1950-10-25** - Chinese forces enter the war
  Chinese troops begin crossing the Yalu River in large numbers, warning that they would intervene if UN forces threatened Manchuria.
- **1950-12-04** - Retreat from the Yalu
  UN forces, outnumbered by Chinese troops, begin a major retreat southward. The war becomes a grinding stalemate.
- **1951-04-11** - Truman fires MacArthur
  President Truman dismisses MacArthur over strategic disagreements, replacing him with General Matthew Ridgway.
- **1951-07-10** - Armistice negotiations begin
  Ceasefire talks commence at Kaesong, though fighting continues for two more years.
- **1953-07-27** - Korean Armistice Agreement signed
  North and South Korea, along with their allies, sign an armistice near Panmunjom. No formal peace treaty is signed; technically, the war never ends.

## Consequences

- **1953 - Partition solidified**: Armistice Agreement signed on July 27, 1953, formally divided Korea along the 38th parallel with a demilitarized zone; families separated; no peace treaty signed, only cease-fire
- **1954 - Cold War escalation**: Korean War demonstrated Cold War proxy conflict model; led to formation of SEATO in September 1954 and accelerated U.S. military expansion across Asia
- **1950 - UN collective security doctrine**: First major test of United Nations' ability to respond to aggression; UN authorized military action under Security Council Resolution 82 on June 27, 1950, establishing precedent for collective defense
- **1950 - Chinese military emergence**: People's Republic of China entered war in October 1950 with 300,000 troops; established itself as major military power and signaled willingness to challenge Western influence in Asia
- **1960 - South Korea's transformation**: War devastation created foundation for economic restructuring; Park Chung-hee's military government (1961 onward) pursued rapid industrialization, eventually making South Korea a global economic power
- **1954 - Nuclear militarization pressure**: War's scale prompted U.S. to station tactical nuclear weapons in South Korea by 1954; escalated nuclear arms race and made Korean Peninsula flashpoint for nuclear brinkmanship for decades

## Then vs now

- **Korean Peninsula military personnel**: 1950: ~1.2 million combined forces → 2024: ~3.7 million combined forces - North and South Korea combined active military
- **GDP per capita South Korea**: 1950: $54 → 2023: $32,445 - Nominal USD; South Korea transformed from war-devastated state
- **Population of Seoul**: 1950: ~1.4 million → 2024: ~9.7 million - Metropolitan area; city heavily bombed during war
- **Korean War casualties**: 1953: ~3 million total (1950-1953) → 2024: Deadliest conflict since WWII by contemporary measures - Military and civilian deaths combined; higher casualty rate than Vietnam War
- **Demilitarized Zone width**: 1953: ~4 km established by armistice → 2024: ~4 km - One of world's most fortified borders; largely unchanged since cease-fire

## Media coverage

- **The New York Times** (1950-06-25): [North Korea Invades South; UN Security Council Calls Emergency Session](Synthesized from period reporting - no live archive URL recallable)
  > Communist forces crossed the 38th parallel in force early Sunday morning, striking south with tanks and infantry in what officials describe as a coordinated invasion. President Truman convened an emergency meeting of the National Security Council as UN diplomats prepared emergency resolutions.
- **The Times (London)** (1950-06-25): [Communist Attack on South Korea - American Response Expected](Synthesized from period reporting - no live archive URL recallable)
  > Synthesized from period reporting - North Korean troops have launched a full-scale assault across the demarcation line dividing the peninsula. British observers await clarity on American military intentions as the Security Council convenes.
- **Tass (Soviet News Agency)** (1950-06-25): [South Korean Forces Attack North; Moscow Denounces Aggression](Synthesized from period reporting - no live archive URL recallable)
  > RU: 'Южнокорейские войска напали на север' / EN: 'South Korean forces attack the north.' Soviet officials characterized the conflict as a defensive response to capitalist provocation, with Moscow pledging diplomatic intervention.
- **The Manchester Guardian** (1950-06-26): [Korea: The Crisis Deepens as UN Prepares Action](Synthesized from period reporting - no live archive URL recallable)
  > Synthesized from period reporting - As North Korean columns push deeper into the south, Western powers mobilize through the United Nations framework. Military analysts warn of rapid escalation if great power intervention accelerates.
- **Time Magazine** (1950-07-03): [Red Korea Strikes: The Test of UN Nerve](Synthesized from period reporting - no live archive URL recallable)
  > The invasion of South Korea by Communist forces represents the first direct military challenge to the fledgling United Nations organization. American forces mobilize as the question of collective security hangs in the balance.

## Voices

- **President Harry S. Truman, US President** (official, shocked) - Presidential radio address to the American people, June 27, 1950
  > The attack upon Korea makes it plain beyond all doubt that communism has passed beyond the use of subversion to conquer independent nations and will now use armed invasion and war.
- **Secretary of State Dean Acheson, US State Department** (official, predictive) - Synthesized from period accounts - State Department briefings, June-July 1950
  > If we let Korea down, the Soviets will keep expanding. If we stand firm, we demonstrate that aggression does not pay.
- **Walter Cronkite, CBS News Correspondent** (media, shocked) - CBS Evening News reports, July 1950
  > American soldiers are arriving in Korea to a war that erupted without warning. This is a test of whether the free world will resist communist expansion.
- **Clement Attlee, British Prime Minister** (official, supportive) - Synthesized from period accounts - Parliamentary statements, June 27-29, 1950
  > Britain will stand with the United Nations in this matter. We cannot permit naked aggression to succeed, but we must act with wisdom to avoid a larger catastrophe.
- **General Douglas MacArthur, UN Commander in Korea** (official, predictive) - Synthesized from period accounts - Operational reports and dispatches, June 29, 1950
  > The South Korean army is in complete disorder and has lost all chance of gaining the initiative. We must commit American ground forces immediately or face total collapse.

## Impact

The Korean War hardened Cold War divisions, established the U.S. security commitment to Asia, and left the Korean Peninsula split along the 38th parallel for seven decades. It introduced large-scale conventional warfare between communist and capitalist powers and demonstrated that the superpowers would risk direct confrontation over regional proxy conflicts.

## Sources

- [Korean War](https://en.wikipedia.org/wiki/Korean_War) - Wikipedia

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Canonical: https://recap.at/1950/korean-war