This document provides an overview of communism spreading in East Asia during the Cold War era. It discusses the communist revolution in China led by Mao Zedong which established the People's Republic of China in 1949. It then examines China's role as a "wild card" in the Cold War and tensions with both the Soviet Union and United States. The document also covers the division of Korea after World War II and the start of the Korean War when North Korea invaded South Korea in 1950, leading to U.S. involvement and China sending troops to aid North Korea. By 1953 an armistice was reached leaving Korea divided along the 38th parallel, with the north remaining communist and the south transitioning to democracy.