As the Roman Empire disintegrated, northern Gaul turned first into a military province and then into a playground for warlords, some Roman and some barbarian. This episode is the story of how one warlord and one group navigated this environment to become the kingdom of the Franks.

Watch a preview of Genius, the new show on National Geographic about Albert Einstein, starring academy award winner Geoffrey Rush: NatGeoTV.com/Genius

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