* _Firebrand:_ _The Life of Horace Greeley_ (2019)
* _Not for All the Gold in Nevada: The Bitter 1876 Campaign of William M. Stewart_ (2014)
* _The Curious Death of Charley Siringo: The Wild West's Most Famous Detective_ (2009)
* _The Eagle's Nest: The Johnson House in Helena and Its People_ (1995, Montana Historical Society)
* _When Hell Froze Over: A Story of Courage and Survival_ (1992, Mountain Press)
Fiction:
* _The Cost of Faith_ (2021)
* _The Road Home: A Novel of the Montana Territory_ (2018)
* _The Song of the Lark: A Novel of the Montana Territory_ (2009, Touchstone)
* _The Winter Wife: A Novel of the Lewis and Clark Expedition_ (2001, Viking)
* _Warped Pass: A Novel of the Blackfeet Indian Nation_ (1995, Penguin/NAL)
* _The Life and Spirit of Montana Sam_ (1989, Penguin)