He is the author of Ghost Dances and Identity: Prophetic Religion and American Indian Ethnogenesis in the Nineteenth Century. He is currently working on An Environmental History of Little Bighorn Battlefield National Monument. The work was commissioned by the National Park Service. He is also working on a book about the way non-Indian doctors dealt with native healers in the era of assimilation. He has published numerous book reviews and articles about Native American history. He is currently serving on the board of editors for Western Historical Quarterly.