<Tr> <Td> <Ul> <Li> </Li> <Li> </Li> <Li> </Li> </Ul> </Td> </Tr> <Ul> <Li> </Li> <Li> </Li> <Li> </Li> </Ul> <P> The division of Korea between North and South Korea occurred after World War II, ending the Empire of Japan's 35 - year rule over Korea in 1945 . The United States and the Soviet Union each occupied a portion of the country, with the boundary between their zones of control along the 38th parallel . </P> <P> With the onset of the Cold War, negotiations between the United States and the Soviet Union failed to lead to an independent and unified Korea . In 1948, UN-supervised elections were held in the US - occupied south only . The anti-communist Syngman Rhee won the election while Kim Il - sung was appointed as the leader of North Korea by Joseph Stalin . This led to the establishment of the Republic of Korea in South Korea, which was promptly followed by the establishment of the Democratic People's Republic of Korea in North Korea . The United States supported the South, the Soviet Union supported the North, and each government claimed sovereignty over the whole Korean peninsula . </P>

When did south korea separate from north korea