Background

Korea had been a Japanese colony from 1910 to 1945. When Japan surrendered, the U.S. and USSR agreed to divide Korea temporarily at the 38th parallel, with Soviet forces accepting Japanese surrender north of the line and American forces south of it. The temporary division hardened into a permanent one as the Cold War intensified. By 1948 two separate Korean states had emerged.

• Democratic People's Republic of Korea (North Korea): Communist, led by Kim Il-sung, aligned with USSR and later China

• Republic of Korea (South Korea): Authoritarian capitalist, led by Syngman Rhee, aligned with the United States