The Buffalo Hunter Hunter by Stephen Jones

Etsy Beaucarne is an academic who needs to get published. So when a journal written in 1912 by Arthur Beaucarne, a Lutheran pastor and her grandfather, is discovered within a wall during renovations, she sees her chance. She can uncover the lost secrets of her family, and get tenure. As she researches, she comes to learn of her grandfather, and a Blackfeet called Good Stab, who came to Arthur to share the story of his extraordinary life. The journals detail a slow massacre, a chain of events charting the history of Montana state as it formed. A cycle of violence that leads all the way back to 217 Blackfeet murdered in the snow. A blood-soaked and unflinching saga of the violence of colonial America, a revenge story like no other, and the chilling reinvention of vampire lore from the master of horror.