Beginning in 1844 with the marriage of Montana fur trader Malcolm Clarke and his Piegan Blackfeet bride Coth-co-co-na, western historian Andrew Graybill traces the family from the mid-19th century, when such mixed marriages proliferated, to the first half of the 20th, as Clarke's children and grandchildren moved back and forth between white and native worlds. At the center of Graybill's history is the virtually unexamined 1870 Marias (or Baker) Massacre, on a par with the more infamous slaughters at Sand Creek and Wounded Knee—an episode set in motion by the murder of Malcolm Clarke by one of his wife's cousins, and in which Clarke's two sons rode with the Second U.S. Cavalry against their own blood relatives.