Which event took place first, Operation Undertone or The Battle of the Ch'ongch'on River?
Battle of the Ch'ongch'on River The Battle of the Ch'ongch'on River, also known as the Battle of the Ch'ongch'on () or the Second Phase Campaign Western Sector (), was a decisive battle in the Korean War, and it took place from November 25 to December 2, 1950, along the Ch'ongch'on River Valley in the northwestern part of North Korea. In response to the successful Chinese First Phase Campaign against the United Nations forces, General Douglas MacArthur launched the Home-by-Christmas Offensive to evict the Chinese forces from Korea and to end the war. Anticipating this reaction, the Chinese People's Volunteer Army Commander Peng Dehuai planned a counteroffensive, dubbed the "Second Phase Campaign", against the advancing UN forces.
Battle of Pyongyang (1950) The Battle of Pyongyang (17–19 October 1950) was one of the major battles of the United Nations and South Korean offensive during the Korean War. Following the Battle of Inchon, the UN forces recaptured Seoul, the capital of South Korea, and proceeded to north of the 38th parallel. Shortly after advancing north, the American and South Korean forces faced the North Korean defensive near Pyongyang, the capital of North Korea, on October 17. Since North Korea's leadership and its main forces had already withdrawn to Kanggye, the allied forces soon captured Pyongyang on October 19.The battle was followed by an airborne assault by the U.S. 187th Infantry Regiment 40km north of Pyongyang, with the intention of cutting off North Korean units retreating from the city.