It's 1861 and Ada Monroe (NICOLE KIDMAN) and her preacher father (DONALD SUTHERLAND) have arrived in Cold Mountain, North Carolina from Charleston. Although local man Teague (RAY WINSTONE) isn't pleased to see them, the likes of Esco (JAMES GAMMON) and Sally Swanger (KATHY BAKER) are, while carpenter W.P. Inman (JUDE LAW) takes an instant liking to Ada.
The feeling is mutual and the two become something of an item, but with the state seceding from the Union, Inman sets off with his Confederate comrades for war. The two correspond through letters, but the years pass, Ada's father dies and Inman is wounded. When he's read one of Ada's letters begging him to come home, the soldier decides to go AWOL.
He then sets out on a long and perilous journey where he meets the likes of Veasey (PHILIP SEYMOUR HOFFMAN), a disgraced minister; Junior (GIOVANNI RIBISI), a volatile backwoods man; Sara (NATALIE PORTMAN), a war widow with a young infant; and recluse Maddy (EILEEN ATKINS) who briefly cares for him.
Back in Cold Mountain, Teague has assumed control with the aid of Bosie (CHARLIE HUNNAM), and tries to convince Ada that she should be with him. Despite her poverty she refuses, putting all of her hope in Inman's return. Meanwhile, she gets help from stranger Ruby (RENEE ZELLWEGER), who offers to work the land in exchange for free room and board.
Although she claims her father is dead, he soon arrives in the form of Stobrod (BRENDAN GLEESON) who's traveling with fellow musicians Pangle (ETHAN SUPLEE) and Georgia (JACK WHITE). As they must deal with Teague's search for deserters, Inman tries to avoid capture so that he can return to Cold Mountain and the woman he hopes he still loves.