China Enters the War
Intervention by Communist China suddenly changed the picture. UN forces began to encounter some Chinese soldiers late in October, 1950. In response to international criticism of its intervention, the Chinese government insisted these forces were volunteers. In November four Chinese armies totaling at least 200,000 struck at the UN forces. An even larger force was ready to strike.
Faced with what MacArthur called an entirely new war, the UN and South Korean armies began a general withdrawal. The 8th Army fell back toward the 38th parallel, while X Corps retreated toward the port of Hungnam.
The march of the 7th Division from near the Yalu, and of the 1st Marine Division from Changjin Reservoir (also called Chosin Reservoir), in intense cold and under constant attack, was effected with great hardship. The retreat was not a rout; with close air support, substantial casualties were inflicted on the Chinese and the retreating forces broke up an enemy army group of 12 divisions. A naval force, headed by the battleship Missouri, ringed Hungnam with a wall of fire as the troops fell back into that port. All were safely evacuated by sea, as well as 100,000 civilian refugees.
The X Corps troops were taken to Pusan, where General Walker planned a counterattack. Walker died in a traffic accident on December 23, and was succeeded by Lieutenant General Matthew B. Ridgway.Chinese intervention created "an entirely new war."
On January 1, 1951, Chinese and North Korean troops launched a massive attack across the 38th parallel. They again captured Seoul, January 4, and forced the 8th Army to retreat 25 miles (40 km) below Seoul. Ridgway then launched a limited counterattack. Killing enemy troops was given priority over gaining ground. By slow, but deadly, advances, aided by superior air power, UN troops regained Seoul on March 14 and held a line just below the 38th parallel. In April, UN forces were again just above the parallel.