The Korean War was one of the most destructive conflicts in history. During its three-year duration (1950-1953), every major Korean city was devastated, and an estimated 2½-3 million people perished. It was the first military action of the Cold War, pitting the Communist forces of North Korea, China, and the Soviet Union against the United States and 20 other member-countries of the United Nations. Nearly 37,000 Americans lost their lives defending South Korea, and more than one million South Koreans (civilian and military) died as a result of intense battles and many months of attrition warfare.