The Korean War began in June 1950 when North Korea invaded South Korea, starting heavy fighting between North Korean and Chinese forces and United Nations forces led by the United States and South Korea. Key battles over the next three years included the Pusan Perimeter, the invasion of Inchon, capture of Seoul, and Chinese intervention on behalf of North Korea. Armistice talks began in 1951 and after much stalemate over prisoner of war issues, a truce ending the fighting was finally signed on July 27, 1953, leaving the Korean Peninsula divided along the 38th parallel.