In “America’s Ancestry Craze,” her 2014 Harper’s cover story on genealogy, genetics, and the stories we tell ourselves about where we come from, Maud Newton writes that her research (“whole weekends spent mired in the U.S. Census, working backward through history”) has sometimes “felt like a sickness.”

What drove her obsession was the sense that being able to trace her ancestral lines back far enough might hold the answers to the mystery of the interplay between inheritance and individuality: “If I dug deeply enough, if I scrutinized my findings hard enough and long enough, I might understand why my mother became a preacher and I became a writer and my father was unable to love me in a normal fatherly way.”

Newton still hasn’t unraveled that mystery, but her vigorous book “Ancestor Trouble: A Reckoning and a Reconciliation” deepens her investigation of both family lore (her maternal grandfather is rumored to have married 13 times, once to a woman who shot him in the gut) and our broader preoccupation with our forebears. Building from the backbone of her Harper’s article, Ancestor Trouble represents decades of research into genealogical records, genetic science, and the cultural history of “ancestor hunger” and reverence — as well as Newton’s own coming to terms with how to face and honor her family history.

Newton begins with her most troubling ancestor: her father, from whom she has been estranged for 20 years. A white supremacist lawyer from the…