The 41st Commando, Royal Marines, numbered about 240 officers and men, all volunteers. The unit had been formed in England in August and flew to Japan on 1 September. There it underwent some training in the use of American-made weapons. Later it made three raids on North Korean rail lines behind the front lines, following the Inch'ŏn landing on the west coast of Korea. In mid-November a decision was made to transfer the commando unit to northeast Korea, where it would be attached to the 7th Marine Regiment and used as a second reconnaissance company.
The commando arrived at Hŭngnam on 20 November and eight days later started north for the Chosin Reservoir. That evening it arrived at Koto-ri, where its commander, Lieutenant Colonel Drysdale, learned that it would continue its journey on the morrow and that he would be commander of a combat task force to open the road to Hagaru-ri.[08-2]