Father Laforgue is a devout Jesuit priest assigned to travel upriver to the distant Huron village of Ihonatiria. Having trained extensively for this dangerous mission, he hopes to bring his faith to the indigenous populations and harbors dreams of achieving martyrdom. His reliance on religious doctrine is tested as he encounters the vast Canadian wilderness and cultures with fundamentally different worldviews.

Daniel is an intelligent European youth just under twenty years old who assists Father Laforgue on his mission. Though promised a future as a fully-fledged Jesuit priest if he completes the journey, he shows a deep fascination with the local indigenous cultures. He learns their languages and mimics their customs, creating a growing ideological divide between himself and his Catholic superiors.

Neehatin is the pragmatic leader of the Algonkin group hired to escort the Europeans to Ihonatiria. He is a careful and politically minded leader who consults his council, his wife, and local sorcerers before making decisions. He accepts the job to acquire muskets for his people, placing their survival and modernization above all other concerns.

Annuka is a young Algonkin woman traveling with Neehatin's group. She possesses a firm understanding of her people's spiritual beliefs and observes the strange behavior of the European travelers with caution. She develops a strong bond with Daniel, encouraging him to abandon his mission and integrate into her community.

Chomina is a senior Algonkin man and Annuka's father. He holds a respected position within Neehatin's council and takes his responsibilities seriously, often advocating for honoring their agreements. He travels with his wife and children, prioritizing their safety during the dangerous winter journey.

Mestigoit is a small, physically deformed Montagnais sorcerer whom the Algonkin revere. He brings an intense spiritual energy to the traveling party, diagnosing ailments and interpreting signs. He immediately identifies Father Laforgue as a hostile spiritual entity, creating a tense religious rivalry on the river.

Father Jerome is a veteran Jesuit stationed at the distant Huron settlement. Having suffered a severe stroke, he is partially paralyzed and physically vulnerable. He faces intense hostility from the local Huron people, who blame his Christian presence for a devastating fever spreading through their community.

Known as the Commandant, Samuel de Champlain is the highest-ranking European official in Québec. He coordinates the expansion of French influence in the region, using trade goods like muskets to secure indigenous cooperation for his religious and political initiatives.

Father Bourque is a senior Jesuit in the Québec settlement who handles administrative duties for the religious order. He oversees the preparation of supplies for the journey to Ihonatiria and serves as a linguistic bridge between the French authorities and the indigenous guides.

Kiotsaeton is the paramount leader of an Iroquois group that ambushes travelers near the rapids. Cloaked in ceremonial beaver skin, he directs his people with ruthless efficiency, viewing the capture of French allies as retaliation for past violent encounters with Europeans.

Taretande is the council chief of the Huron village. He attempts to manage the devastating sickness sweeping his community by treating with the Jesuits, weighing the cultural cost of converting to Christianity against the immediate physical survival of his people.

Ondesson is the war chief of the Huron village of Ihonatiria. He takes an aggressive stance against the Jesuit missionaries, viewing them as dangerous witches responsible for the fatal fever decimating his community.

The unnamed wife of Chomina travels alongside her husband and children during the escort mission. She endures the brutal winter conditions of the Canadian wilderness while helping maintain the family's habitation and supplies.

Chomina's young, unnamed son accompanies his parents and older sister on the river journey. His presence highlights the family-oriented nature of the Algonkin traveling parties and the vulnerable position they occupy in disputed territories.

Casson is a French fur trader who operates in the wilderness. He is deeply concerned about protecting his commercial interests and maintaining good relations with his indigenous guides, prioritizing his own safety over assisting desperate travelers.

Vallier is a French fur trader who shows slightly more charitable inclinations than his partner. He provides food and supplies to the starving travelers in exchange for a receipt to be redeemed later in Québec.