Roman Britain fell fast, and it fell hard. Into the ruins of this world stepped a wave of migrants from the North Sea coast of the Continent whom we know as the Anglo-Saxons. This migration, a complex and dynamic movement of people over the course of 200 years, rewrote the political, demographic, linguistic, and cultural maps of eastern Britain, transforming it into England. Watch a preview of Genius, the new show on National Geographic about Albert Einstein, starring academy award winner Geoffrey Rush: NatGeoTV.com/Genius Take the survey at wondery.com/survey. See Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.