A country of northeast Asia on the Korean Peninsula. Inhabited since ancient times, the region was occupied by Japan from 1910 until the end of World War II in 1945. After the war the peninsula was divided into a Soviet occupation zone in the north and an American zone in the south. The territory attained its present-day boundaries after the cease-fire ending the Korean War (1950-1953). Under Kim Il Sung (ruled 1948-1994) North Korea became increasingly isolated, especially after the breakup of the Soviet Union in 1991. Pyongyang is the capital and the largest city.