Death comes riding - Terrell L. Bowers

Lucas usually avoided contact with the Indians, but fate sometimes stepped in. When a simple job turns out to be a death ride, his relationship with one Indian in particular changes his life forever. In the midst of an impending war between the assembled tribes of the Black Hills and the army, Lucas partners Daniel Brooks, a half-Cheyenne who doesn't really belong on either side of the war. Daniel helps Lucas seek out the men who robbed and shot him, and then left him for dead. Then there is Iris Ducane, the girl who captured Lucas's heart, already being courted by Captain Bagot, a suave Creole Frenchman from the nearby fort, who wants her for himself-and he is willing to kill Lucas to win her hand!