Simon is a fifteen-year-old boy from Missouri who conceives a bold business plan to herd one thousand bronze turkeys nearly a thousand miles to Denver. Though his relatives dismiss him as a simple-minded burden, he possesses deep practical wisdom and an innate understanding of animal behavior. He builds an unconventional team of societal outcasts, relying on fairness and empathy to lead the expedition across the American West.

Bidwell is an experienced mule skinner who struggles with an alcohol addiction following the tragic loss of his wife and three children to cholera. Simon finds him and offers a formal partnership in the turkey drive. He brings essential trail knowledge to the group, managing the wagon and offering worldly advice while acting as a reliable, paternal figure to Simon.

Jabeth is a starving fifteen-year-old orphan fleeing enslavement and seeking freedom in the Kansas Territory. Initially terrified of the turkey flock, he soon proves his immense value as the group's official provisioner. He uses a borrowed knife to hunt, fish, and forage, ensuring the camp's survival while developing a strong bond of friendship with his fellow travelers.

Lizzie is a sixteen-year-old girl who survives the loss of her entire family on the harsh prairie. Simon and his crew take her in after their turkey flock devours an incoming swarm of grasshoppers. She firmly pushes back against Simon's overprotective instincts, demanding the right to contribute daily work by identifying useful plants and harvesting peat for fuel.

Samson is a traveling circus performer who bills himself as the strongest man in the world, and he is also Simon's estranged father. He abandoned his son a decade prior following the death of Simon's mother. Driven entirely by greed and opportunism, he feigns paternal affection only after discovering the immense financial potential of Simon's turkey enterprise.

Miss Rogers is Simon's third-grade teacher who perceptively recognizes that his true talents lie outside of formal academics. She encourages him to find his own path in the world. She demonstrates extraordinary faith in her former student by investing her entire life savings of 250 dollars into his unconventional turkey-driving venture.

Simon's extended relatives, primarily his Aunt Maybelle, Uncle Lucas, and Cousin Ned, view the teenager as a simple-minded burden. They eagerly liquidate his small inheritance in exchange for an old wagon and mules. They demand a legally binding contract to ensure they are rid of him permanently, representing the unsupportive environment Simon leaves behind.

Cleaver is a cynical con man who cheats Simon out of fifty cents during a circus game. He subscribes to a predatory philosophy where intelligent people take money from the gullible. He quickly allies with Samson Green to track the expedition and steal Simon's valuable flock.

John Winter Prairie leads a group of Pottawatomie men in the Kansas Territory. He operates with a strict code of honor and mutual respect, peacefully accepting a camp breakfast as fair restitution when Simon's group accidentally trespasses on his people's land.

Mr. Buffey is a local neighbor who inadvertently inspires the entire journey. He casually mentions to Simon that turkeys sell for practically nothing locally but fetch five dollars a head in the boomtown of Denver, prompting Simon to negotiate for one thousand bronze birds.

Emmett is Mr. Peece's dog. He travels alongside the wagon on the long journey to the Rocky Mountains, helping to spook the turkey flock when necessary and providing steady companionship to his owner.

Captain Masters is a United States Cavalry officer stationed on the frontier. When his men arbitrarily shoot one of Simon's turkeys for sport, the captain restores order but treats the incident bureaucratically, suggesting Simon file an official reimbursement claim for the dead bird.

Lila is a performer traveling with the circus and Samson Green's romantic partner. She makes a brief appearance while Samson is attempting to explain his decade-long absence to his son.