How accurate is 'The Northman' to Viking history? Well, it’s a Robert Eggers film.

A brutal hockey-like sport played to the death. Berzerkers dancing and screaming 'til dawn pre-raid. Shallow, stealthy longboats. Though the narrative may be the stuff of legend, the Viking Age detail in The Northman is rooted in history, and writer-director Robert Eggers took pains to get it as close to the real deal as...