9th Army Group's 20th army divided and encircled two Marine regiments near the Changjin (Chosin) reservoir. In one of the proudest battles of Marine Corps history, they fought out of the trap, reducing the Chinese divisions to ineffectiveness for the critical time Eighth Army needed to complete its retreat and reform at the 37th parallel.
9th Army Group's 20th army basically ambushed two Marine regiments at Chosin and virtually destroyed 32RCT's Task Force MacLean/Faith. However, the Marines did fight out of the trip and they and the rest of X Corp withdrew safely to Hungnam, where 105,000 fighting men and 90,000 civilians were evacuated by Our Navy.