THE WORLD ATLAS

War · 25 June 1950 – 27 July 1953

Korean War

Korea, a Japanese colony from 1910, was divided at the 38th parallel into Soviet and US occupation zones in 1945, and in 1948 rival governments formed: Kim Il Sung's communist North and Syngman Rhee's South. On 25 June 1950 North Korea invaded the South and quickly took Seoul.

The UN Security Council called on members to help South Korea, and a US-led United Nations Command was formed. After being pushed back to a perimeter around Pusan, UN forces landed at Incheon in September, retook Seoul and advanced deep into the North. In October China entered the war, driving the UN back south of Seoul by January 1951. The front then stabilised near the 38th parallel, and from July 1951 two years of trench warfare accompanied armistice talks, stalled largely over the return of prisoners. The armistice of 27 July 1953 left Korea divided along a demilitarised zone; no peace treaty has been signed.

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Dates
25 June 1950 – 27 July 1953
Casualties
An estimated 2.5 to 4 million people died, including about one million soldiers and 1.5 to 3 million civilians.

The sides

South Korea and the UN Command

North Korea and China

Timeline of the Korean War

  1. North Korea invades South Korea

    After years of border clashes, and with Soviet approval and equipment, the Korean People's Army attacked across the 38th parallel before dawn on 25 June 1950 with tanks and artillery. South Korea's smaller, lightly armed army was caught unprepared and fell back along the whole front. The UN Security Council, which the Soviet Union was boycotting, passed resolutions condemning the invasion and calling on members to help repel it.

  2. Seoul falls

    Three days into the invasion, North Korean troops entered Seoul, the South's capital. South Korean engineers blew up the bridges over the Han River while they were still crowded with soldiers and refugees, trapping much of the army north of the river. On 27 June President Truman had ordered US air and naval forces to support South Korea, and he soon committed ground troops from the occupation forces in Japan.

  3. First US ground troops fight at Osan

    Task Force Smith, a small battalion-sized force flown in from Japan, met the North Korean advance near Osan, south of Seoul, on 5 July. Lacking effective anti-tank weapons, it was overrun by T-34 tanks and infantry and forced into a disorderly retreat. The defeat showed that the US garrison troops in Japan were neither trained nor equipped for the war, and UN forces continued to fall back south through July.

  4. UN forces hold the Pusan Perimeter

    By early August South Korean, US and newly arriving British troops were confined to a corner of south-east Korea around the port of Pusan, behind a line along the Naktong River. For six weeks they fought off repeated North Korean attacks while reinforcements and supplies poured in through the port. The North Korean army, at the end of long supply lines under constant air attack, was steadily worn down.

  5. UN amphibious landing at Incheon

    General Douglas MacArthur, commander of the UN forces, staged a risky amphibious landing at Incheon, the port of Seoul, far behind North Korean lines, despite its extreme tides. US Marines and army troops came ashore on 15 September, and on 16 September the Eighth Army broke out of the Pusan Perimeter. Caught between the two forces, the North Korean army collapsed and its remnants retreated north.

  6. UN forces recapture Seoul

    After a week of hard street fighting, US Marines and South Korean troops retook the ruined capital in late September, and Syngman Rhee's government returned on 29 September. Thousands of North Korean soldiers were cut off in the South. The UN now faced a choice: stop at the 38th parallel, restoring the pre-war border, or pursue the beaten North Korean army and reunify the peninsula by force.

  7. UN forces cross the 38th parallel

    South Korean troops crossed into the North on the east coast around 1 October, and US-led UN Command forces followed on 7 October after the UN General Assembly endorsed the goal of a unified Korea. China had warned through Indian diplomats that it would intervene if American troops crossed the parallel, but the warnings were largely dismissed in Washington and Tokyo.

  8. UN forces capture Pyongyang

    On 19 October US and South Korean troops, together with the British 27th Commonwealth Brigade, entered Pyongyang, the North Korean capital, as Kim Il Sung's government fled north. UN columns then pushed towards the Yalu River, China's border, spreading out over mountainous terrain as winter approached. Many commanders expected the war to be over by Christmas, and planning began for the occupation of a reunified Korea under the South's government.

  9. Chinese troops cross the Yalu into Korea

    The same day Pyongyang fell, the first units of the Chinese People's Volunteer Army, commanded by Peng Dehuai, began crossing the Yalu River secretly at night. Mao Zedong had decided to intervene to keep American forces from China's border. On 25 October the Chinese launched their first offensive against South Korean and US units, then briefly withdrew, leaving UN commanders uncertain of their numbers.

  10. Battle of Chosin Reservoir

    In late November massive Chinese forces struck the UN advance. On 27 November they surrounded the US 1st Marine Division and army units around the Chosin Reservoir in north-east Korea. In temperatures far below freezing, the encircled troops fought their way out over 17 days to the coast. Further west the Eighth Army was routed and made the longest retreat in US Army history.

  11. Hungnam evacuation completed

    The UN X Corps established a defensive perimeter around the north-eastern port of Hungnam on 11 December. By 24 December some 100,000 troops and tens of thousands of North Korean civilian refugees had been evacuated by sea to the South, and the port facilities were demolished. By the end of December UN forces had abandoned the whole of North Korea.

  12. Communist forces retake Seoul

    Chinese and North Korean forces launched a New Year offensive across the 38th parallel, and on 4 January 1951 Seoul changed hands for the third time as UN troops withdrew south of the Han River. Hundreds of thousands of civilians fled south again. General Matthew Ridgway, who had taken command of the Eighth Army after its commander was killed in an accident, restored its morale and halted the retreat.

  13. UN forces recapture Seoul in Operation Ripper

    Ridgway's methodical counter-offensives used massed firepower to inflict heavy losses on the over-extended Chinese forces. Operation Ripper, launched on 7 March, retook Seoul on 14 March, leaving the city in ruins after its fourth change of hands in less than a year. By the end of March UN forces were back near the 38th parallel, roughly where the war had started nine months earlier.

  14. Truman relieves MacArthur of command

    MacArthur publicly called for expanding the war to China, including attacks on Chinese bases, contradicting Truman's policy of a limited war confined to Korea. On 11 April 1951 Truman dismissed him from all his commands in Tokyo, from which he had directed the war, and replaced him with Ridgway. The decision caused uproar in the United States but confirmed civilian control over military policy.

  15. Chinese spring offensive; Battle of the Imjin River

    On 22 April the Chinese launched their largest offensive of the war. On the Imjin River north of Seoul, the British 29th Brigade held its positions for three days before retreating; the 1st Battalion, Gloucestershire Regiment, was surrounded on Hill 235 and most of its men captured. At Kapyong, Australian and Canadian battalions also blocked the advance. The offensive failed to retake Seoul.

  16. Armistice talks open at Kaesong

    With the front stabilised near the 38th parallel, negotiators from both sides met at Kaesong on 10 July 1951; the talks later moved to Panmunjom. They dragged on for two years, deadlocked above all over prisoners of war: thousands of Chinese and North Korean prisoners did not want to go home, and the UN refused forced repatriation. Meanwhile both armies dug in along a front of trenches and fortified hills, fighting costly battles for small gains.

  17. Armistice signed at Panmunjom

    After the death of Stalin in March 1953 and a compromise on prisoners based on an Indian proposal, the armistice was signed at Panmunjom on 27 July 1953. It created a demilitarised zone about 4 kilometres wide along the final front line, which left the South with a little more territory than before the war. South Korea did not sign. No peace treaty followed, and Korea remains divided.

Related

Other wars of the time

Sources