Covers the entire era that could be called "Viking" from the days of Charlemagne to the final Christianization and end of the raids.
Religion was front and center for a lot of it. A lot of violence, invasion, enslavement, and conquest. Discusses artifacts, such as grave goods, and laws, but any details about daily life are incidental. Much about kings and the conflicts ensuing there, too.
At one point, he notes no genetic difference between the Danes and Anglo-Saxons -- which claim he was reading into a document that didn't have it, I think. But the rest covers a lot of facts.