Ravenous

Ravenous is a 1999 CzechAmerican black comedy horrorsuspense film directed by Antonia Bird and starring Guy Pearce, Robert Carlyle, Jeffrey Jones and David Arquette. The film revolves around cannibalism in 1840s California and some elements bear similarities to the story of the Donner Party and that of Alferd Packer. Screenwriter Ted Griffin lists Packers story, as recounted in a couple of paragraphs of Dashiell Hammetts The Thin Man, as one of his inspirations for Carlyles character.

During the MexicanAmerican War 1846 1848, Second Lieutenant Boyd, who is fighting in the United States Army, finds his courage fail him in battle so he plays dead as his unit is massacred. His body, along with the other dead are put in a cart and hauled back to the Mexican headquarters throughout this journey blood drips into Boyds mouth. However, in a moment of bravery, Boyd seizes the chance to capture the Mexican HQ. His heroism earns him a Captains promotion but when General Slauson learns of the cowardice through which victory was achieved he posts Boyd into exile at Fort Spencer, a remote military outpost high in the Sierra Nevadas.Shortly after Boyd joins the sevenman garrison at Fort Spencer, a stranger named Colqhoun arrives and describes how his wagon train became lost in the mountains. A Colonel Ives had promised the party a shorter route to the Pacific Ocean but instead had led them on a more circuitous route resulting in the party getting trapped by snow. People were reduced to cannibalism to avoid starvation. A rescue party is assembled to search for survivors. But before they leave they are warned by their Native American scout, George, of the Wendigo myth anyone who consumes the flesh of their enemies takes their strength but becomes a demon cursed by an insatiable hunger for more human flesh. ........

Source: Wikipedia