Korean War conflict, 1948-1953

Series of five maps showing the course of the Korean War conflict from 1948 to 1953.

In August 1945, as the Second World War ended, Soviet forces advanced along the Japanese-occupied Korean peninsula to the agreed line of demarcation with the American occupation zone, the 38th parallel. In September, American forces landed in the southern part of Korea. In 1948, the United Nations (UN) oversaw the formation of the Republic of Korea in the south. The Soviet Union responded by establishing a communist regime – the Democratic People’s Republic of Korea – in the north. Both governments claimed sovereignty over all Korea.

June–September 1950
In June 1950, North Korea invaded the south. Seoul fell immediately, and North Korean forces pushed south towards the port of Pusan (Busan). American troops from Japan helped halt the North Koreans at Taegu (Daegu), 80 kilometres from Pusan.

September–November 1950
In September 1950, UN forces led by American General Douglas MacArthur landed at In’chon and quickly liberated Seoul. The North Korean army retreated northwards. Following the In’chon success, the UN sought to unify Korea by force, ignoring the threat of intervention by the People’s Republic of China, which had been created the previous year.

November 1950–January 1951
As UN forces pushed north, thousands of Chinese troops entered North Korea. In November 1950, they inflicted a major defeat on the UN forces and forced them to retreat. In January 1951, Seoul fell to the Chinese, who advanced as far as Cho’nan (Cheonan), 85 kilometres further south.

January 1951–July 1953
UN forces launched a series of offensives, retaking Seoul and pushing the Chinese back across the 38th parallel. A series of communist offensives regained some of this lost territory. Units of New Zealand’s Kayforce fought a successful defensive action at Kap’yong in April 1951. Another UN advance carried the front line roughly back to the 38th parallel, where a stalemate developed from July 1951. UN forces occupied this front line – similar to a hilly Western Front – until an armistice ended the fighting two years later. Negotiators were unable to broker a peace settlement and, officially, the two Koreas remain at war.