One thing the show doesn't do is propose a theory for why the Vikings decided to conquer the world. It provides a theory for how they went west, but not a why. The Viking invasions of Europe changed the face of the entire continent, and particularly England and Ireland. A backward, sparsely populated, frigid corner of Europe sent forth swarms of raiders and settlers that got as far as Constantinople, Kiev, and Greenland. I know there is no answer because the vikings did not have a written language, but I would have thought a show about Vikings would at least make a guess.