History of Korea
After the end of WWII in 1945, the Allies divided the country into a northern area (protected by the Soviets) and a southern area protected (primarily by the United States). In 1948, when the powers failed to agree on the formation of a single government, this partition became the modern states of North and South Korea. The peninsula was divided at the 38th Parallel: the "Republic of Korea" was created in the south, with the backing of the US and Western Europe, and the "Democratic People's Republic of Korea" in the north, with the backing of the Soviets and the communist People's Republic of China. The new premier of North Korea, Kim il-Sung, launched the Korean War in 1950 in an attempt to reunify the country under Communist rule. After immense material and human destruction, the conflict ended with a cease-fire in 1953. The two nations officially remain at war because a peace treaty was never signed. In 1991, both states were accepted into the United Nations.
South Korea
There were no formal diplomatic ties between South Korea and Japan directly after independence the end of World War II in 1945. South Korea and Japan eventually signed the Treaty on Basic Relations between Japan and the Republic of Korea in 1965 to establish diplomatic ties. There is heavy anti-Japanese sentiment in South Korea because of a number of unsettled Japanese-Korean disputes, many of which stem from the period of Japanese occupation after the Japanese annexation of Korea. During World War II, more than 100,000 Koreans served in the Imperial Japanese Army. Korean women were coerced and forced to serve the Imperial Japanese Army as sexual slaves, called comfort women, in both Korea and throughout the Japanese war fronts.