The mythology of the Vikings is still alive today in popular culture: everyone knows of Thor, the Norse god of war (made popular through the Marvel Cinematic Universe); Ragnarök, the great battle at the end of the world, where many gods and heroes perish and the earth is submerged in water; the tragic love story of Siegfried and Brunhild, central to the music and operas of German composer Richard Wagner; the characters of Loki the Trickster, the great god Odin’s eight-legged horse Sleipnir, and elves, dwarfs and trolls, all popular motifs in 20th century fantasy literature. In Norse Gods &...