Battle of Chosin Reservoir One of the most well-known campaigns in the Korean War is the Battle of Chosin Reservoir during the dates of November 26th- December 11th, 1950. The battle was fought in some of the most extreme cold temperatures with the lowest being recorded at a -54⁰ F. This battle was between Communist Chinese and United Nations (UN) who had the help of the United States Marines. The Communist Chinese wanted to completely annihilate their enemy. They wanted to do so by surrounding the UN troops who were located in the Chosin mountainous area under severe cold weather with blinding snowstorms. The UN with the aid of the US Marine Divisions had to form a withdrawal plan and could only use the Main Supply Route (M.S.R.). The M.S.R. was a single narrow unpaid road which they would be traveling for 88km (55miles).…show more content… However, at the same time Communist Chinese forces began pouring across the border. US X Corps were held up in northeastern Korea and unable to support. Ninth Army Group of the People Liberation Army (PLA) crippled the X Corps advance to help and swarmed around the UN troops at Chosin. Major General Ned Almond, commander of the US X Corps, was aware of what was about to happen. He then ordered Gen Oliver P. Smith, commander of the 1st Marine Division, to begin fighting to retreat back towards the coast. Commencing on November 26th, Smith’s men endured extreme cold and severe weather. 5th and 7th Marines attacked from their positions near Yudam-ni located along the west bank. The next three days 1st Marine Division successfully defended their positions at Yudam-ni and Hagaru-ri. On November 29th Smith contacted Colonel Lewis B. “Chesty” Puller, commanding 1st Marine Regimentm at Koto-ri and asked him to assemble a task force to re-open the M.S.R. which was the road from there to