Chinese Second Phase Offensive

Sat, 11/25/1950 - Sun, 12/24/1950

The United Nations Command (UNC) had failed to detect the very large number of Chinese PVA formations that had crossed into North Korea. When, on 24 November 1950, the UNC had launched the Eighth Army in the west and its X Corps in the east, on what was known as the 'Home-by-Christmas' offensive, it believed that the UNC forces outnumbered the enemy forces.

When the Chinese Second Phase Offensive was suddenly launched by the PVA against the UNC on 25 November 1950, it resulted in major battles at the Ch'ongch'on River in the west and the Chosin Reservoir in the east. These battles were fought in temperatures as low as −30 °C (−22 °F) and cold injuries possibly accounted more for the heavy casulties than did combat injuries.

Thirty divisions of Chinese troops, rather than the twelve assumed, attacked the UNC forces with shock effect. Within weeks, ROK units, including whole divisions, had been destroyed. The US 2nd Infantry Division was rendered combat ineffective, losing a third of its men and nearly all of its equipment. Parts of 7th Infantry Division in X Corps on the east were similarly hammered, and it looked for a time as if the Chinese would succeed in encircling and even destroying 1st Marine Division and the units attached to it, including some remnants of 7th Infantry Division and accompanying British units.

Over the next two months, UN forces would retreat some 200 miles, losing not only Pyongyang but Seoul to the enemy for the second time in the war and the Chinese recaptured nearly all of North Korea by the end of the Offensive on 24 December 1950.