Conflict4 January 1951
January 4th Retreat
A Chinese offensive forced South Korean and UN forces to abandon Seoul again. After Seoul was retaken in March 1951 the front stabilized near the 38th parallel.

Cpl. Walter Calmus. (Army) · Public domain · Source
On 4 January 1951 a Chinese and North Korean offensive forced the government and the South Korean and UN forces to leave Seoul again, and many refugees fled south.
Counter-attacking, they retook Seoul in March 1951. The front then moved back and forth near the 38th parallel, and armistice talks began in July 1951.