The year is 1850, and young Sul Ross of Waco, Texas, is ambitious to be a soldier. But his father, landowner Shap Ross, is determined that older brother Pete will be the soldier, and Sul, a farmer. When his father accuses him of lying and twice gives him a hiding without listening to Sul's side of the story, the boy runs away to live in the Anadarko camp of Chief José María, a camp at peace with its Texas neighbors. Sul's adventures really begin when his childhood hero, Sergeant Hanse Mason (the Uncle Comanche of the title), tracks him down. Together they fight off a Kickapoo attack, visit a Comanche village, and rescue ferry passengers from a flash flood.

Lawrence Sullivan Ross, who grew to be not only a ranger but a state senator and governor of Texas, is perhaps now best known for leading the ranger party which rescued Cynthia Ann Parker. Uncle Comanche, based on real incidents from his youth, presents an accurate yet exciting picture of life in frontier Texas. If Sul Ross never had an Uncle Comanche, he should have!