In the winter of 208, Lü Meng participated in the Battle of Red Cliffs, in which the allied forces of Sun Quan and Liu Bei defeated the forces of the northern warlord Cao Cao at Wulin (烏林; in present-day Honghu, Hubei). Cao Cao perfunctorily retreated to northern China, leaving behind his general Cao Ren to defend Nan Commandery (南郡; around present-day Jingzhou, Hubei). Sun Quan's forces, led by Zhou Yu and Cheng Pu, pressed on their attack and besieged Cao Ren in Nan Commandery.