A new book can send you back to an old one, showing you something about who you are and how you got to be that way. That’s what happened to me recently when I read Nancy Marie Brown’s “Song of the Vikings,” a lively new retelling of the life of the 13th-century Icelander Snorri Sturluson.
Brown calls Snorri “the Homer of the North — and also its Herodotus.” A gouty fat man “prone to soaking long hours in his hot tub while sipping stout ale,” Snorri was a shrewd businessman and lawyer, but his lasting fame rests on the books he’s credited with writing: “Egil’s Saga,” a paleo-noir tale starring the murderously capable Egil Skallagrimsson; “Heimskringla,” a history of the kings of Norway; and “The Prose Edda,” which is the principal source of what we know about Norse mythology. Brown also traces Snorri’s influence through the ages, showing how his work was seized on by Richard Wagner and J.R.R. Tolkien, Scandinavian nationalists and Nazi ideologues, metalheads and Aquarians.