William is a young Harvard dropout who comes to the western frontier seeking spiritual clarity and connection with the natural world. Raised by a Unitarian minister, he is inspired by transcendentalist philosophy and desires an authentic experience away from his structured, eastern upbringing. He uses his funds to finance a buffalo hunting expedition, hoping the raw wilderness will provide him with a deeper sense of identity and purpose.

Miller is a seasoned, highly skilled buffalo hunter with an intense, almost obsessive personality. He operates with rigid independence and claims to know the location of a massive, untouched herd of buffalo hidden deep in the Colorado mountains. As the leader of the expedition, he expects absolute compliance and drives his men with quiet but unyielding determination.

Fred is an expert buffalo skinner who possesses a pragmatic, cautious approach to wilderness survival. Unlike the idealistic William or the obsessive Miller, Fred prioritizes self-preservation and monetary compensation, demanding his pay in advance before joining the hunt. He functions as the group's primary voice of reason and frequently questions Miller's risky decisions.

Charley is an older, one-handed wagon driver and camp cook who travels exclusively with Miller. Having lost his hand to frostbite on a previous expedition, he bears the physical scars of the frontier's harsh conditions. He relies heavily on alcohol to cope with his anxieties but constantly carries and reads a Bible, seeking spiritual comfort in the vast, unforgiving environment.

J. D. McDonald is a buffalo hide trader and prominent merchant in the town of Butcher's Crossing. He previously attended the Boston church where William's father preaches and attempts to offer the young man clerical work instead of fieldwork. Recognizing the brutal reality of the hide trade, he tries to warn William against joining the hunters, viewing the enterprise as a destructive force.

Francine is a sex worker who operates in the rough frontier settlement of Butcher's Crossing. She is observant and direct, quickly recognizing that William differs significantly from the hardened, weathered men who usually populate the town. She forms a gentle, uneasy bond with the young easterner before he departs for the mountains.