United States in the Korean War

The military history of the United States in Korea began after the defeat of Japan by the Allied Powers in World War II. This brought an end to 35 years of Japanese occupation of the Korean peninsula and led to the peninsula being divided into two zones; a northern zone occupied by the Soviet Union and a southern zone occupied by the United States. After negotiations on reunification, the latter became the Republic of Korea or South Korea in August 1948 while the former became the Democratic People's Republic of Korea or North Korea in September 1948.

Source: Wikipedia — United States in the Korean War (CC BY-SA 4.0)