Curated timeline

Korean War

The 'Forgotten War' that divided a peninsula. Details the North Korean invasion, the UN intervention led by the US, the Chinese counterattack, and the enduring armistice.

• Division of Korea at 38th Parallel (August 10, 1945)

  U.S. and Soviet forces divide Korea at 38th parallel, creating foundation for future conflict.

• North Korean Invasion (June 25, 1950)

  North Korean People's Army invades South Korea across 38th parallel, beginning Korean War.

• UN Security Council Resolution 82 (June 25, 1950)

  UN condemns North Korean invasion and calls for immediate withdrawal.

• Fall of Seoul (June 28, 1950)

  North Korean forces capture Seoul, forcing South Korean government to flee south.

• Truman Orders US Forces to Korea (June 30, 1950)

  President Truman authorizes use of US ground forces in Korean conflict.

• Battle of Osan (July 5, 1950)

  First engagement between US and North Korean forces results in US defeat.

• Establishment of Pusan Perimeter (August 4, 1950)

  UN forces establish defensive line around Pusan to prevent complete defeat.

• Inchon Landing (September 15, 1950)

  MacArthur's amphibious assault at Inchon outflanks North Korean forces.

• Second Battle of Seoul (September 25, 1950)

  UN forces recapture Seoul from North Korean occupation.

• UN Forces Cross 38th Parallel (October 1, 1950)

  UN forces pursue retreating North Koreans beyond original border.

• Chinese Warning to UN (October 3, 1950)

  Zhou Enlai warns China will intervene if UN forces approach Chinese border.

• First Chinese Attacks (October 25, 1950)

  Chinese People's Volunteer Army launches surprise attacks against UN forces.

• Chinese Massive Intervention (November 25, 1950)

  300,000 Chinese troops launch massive offensive against UN forces.

• Battle of Chosin Reservoir (November 27, 1950)

  US Marines fight desperate retreat in brutal winter conditions against Chinese forces.

• Evacuation of Hungnam (December 24, 1950)

  Largest military evacuation in US history removes UN forces from North Korea.

• Third Battle of Seoul (January 4, 1951)

  Chinese and North Korean forces recapture Seoul in winter offensive.

• Operation Thunderbolt (January 25, 1951)

  UN counteroffensive begins to push Chinese forces back north.

• Operation Killer (February 21, 1951)

  UN offensive focuses on inflicting maximum casualties on Chinese forces.

• Fourth Battle of Seoul (March 14, 1951)

  UN forces recapture Seoul for the final time in the war.

• MacArthur's Dismissal (April 11, 1951)

  Truman fires MacArthur for insubordination and advocating war with China.

• Chinese Spring Offensive (April 22, 1951)

  Largest Chinese offensive of the war fails to break UN lines.

• Battle of the Imjin River (April 22, 1951)

  British forces make heroic stand against Chinese assault, earning lasting fame.

• Start of Armistice Talks (July 10, 1951)

  Ceasefire negotiations begin at Kaesong between UN and Communist forces.

• Battle of Bloody Ridge (August 18, 1951)

  Costly UN assault captures strategic height from Chinese forces.

• Battle of Heartbreak Ridge (September 13, 1951)

  Month-long battle demonstrates futility of costly frontal assaults.

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