https://www.state.gov/u-s-relations-with-the-republic-of-korea
WebSep 22, 2020 · On June 25, 1950, North Korean forces invaded the ROK. Led by the United States, a United Nations coalition of 16 countries undertook its defense. Following China’s entry into the war on behalf of North Korea later that year, a stalemate ensued for the final two years of the conflict until an armistice was concluded on July 27, 1953.