
History of the Korean War United Nations Command (UNC) was established on July 7, 1950 following the United Nations' recognition of North Korean aggression against South Korea. UNC signifies the world’s first attempt at collective security under the United Nations system. United Nations Security Council Resolutions 83 and 84 provided the international legal authority for member states to restore peace on the Korean Peninsula, and they designated the United States as the leader of the unified command we know as UN Command. During the Korean War and the reconstruction period following the signing of the Armistice Agreement, twenty-two countries contributed either combat forces or medical assistance to support South Korea under the United Nations flag.