Vikings

In the autumn of 911, Charles the Simple gave the Viking warlord Rollo a stretch of land around Rouen he could not defend anyway. No copy of the deal survives, and the best account of it was written a century later by a chronicler paid to flatter Rollo's descendants. Out of that shaky record came Normandy, and eventually England's ruling class.

On 8th June 793, Norse raiders struck the monastery at Lindisfarne off the Northumbrian coast. The English had no framework for what had hit them and no immediate answer to it. What followed reshaped the language, the genetics, and the political geography of the British Isles for centuries.