I spent a lot of time this year learning about the religion in which I was raised. I wasn’t alone: the nomination of a certain presidential candidate guaranteed that many people would read up on Mormonism. What were they reading? Over the summer, a Mormon historian who has written a few pieces for me at Slate pointed out that the top-selling book in the Mormonism category at Amazon — after the Kindle edition of the Mormon scriptures, that is — has been, for pretty much eight years straight, Under the Banner of Heaven, by Jon Krakauer. This jibed with my experience: It’s typically the only book about the religion that my secular, left-leaning friends have read.