Sin Killer by Larry McMurtry

The Berrybender Narratives, Book #1 This humorous and dramatic tale begin in 1830, as the Berrybender family, an affluent, British clan, travels up the Missouri river to experience the great American west. Indian raids, buffalo stampedes, chaotic encounters with pioneers, and a preacher called the "Sin Killer" give them more than they bargained for in their journey, and might cost them their daughter.

Now in trade paperback for the first time--McMurtry's' bestselling Berrybender Narratives quartet, which follows the adventures of a noble English family as they travel the Missouri River in 1832 to explore the American frontier.