A war fought between North Korea and China on one side, and South Korea, the USA, and United Nations forces on the other. From the time of their foundation in 1948, relations between North and South Korea were soured by rival plans for unification, and on 25 June 1950 war finally broke out with a surprise North Korean attack that pushed US and South Korean forces far south towards Pusan by September. In the temporary absence of the Soviet representative, the Security Council asked members of the UN to furnish assistance to South Korea. On 15 September US and South Korean forces, under command of General MacArthur, launched a counter-offensive at Inchon, and by the end of October UN forces had pushed the North Koreans all the way back to the Yalu River, the frontier with the People’s Republic of China. Chinese troops then entered the war on the northern side, driving south to recapture the South Korean capital of Seoul by January 1951. After months of fighting, the conflict stabilized in near-deadlock close to the original boundary line (the 38th parallel). Peace negotiations, undertaken in July 1951 by General M. B. Ridgway (who had succeeded MacArthur in April of that year), proved difficult, and it was not until 27 July 1953 that an armistice was signed at Panmunjom and the battle line was accepted as the boundary between North and South Korea.