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.
Korean nationalism
Korean reunification (Korean: 남북통일) refers to the hypothetical future reunification of North Korea and South Korea under a single government. South Korea had adopted a sunshine policy towards the North that was based on the hope that one day, the two countries would be re-united in the 1990s. The process towards this was started by the historic June 15th North–South Joint Declaration in August 2000, where the two countries agreed to work towards a peaceful reunification in the future. However, there are a number of hurdles in this process due to the large political and economic differences between the two countries and other state actors such as China, Russia, and the United States. Short-term problems such as a large number of refugees from the North migrating into the South and initial economic and political instability would need to be overcome.