Actually, they weren't. They were hairy Danish thugs who only spoke French (of a sort), who had followed Rollie the Ganger down from Jutland to squat on the French in the ninth century.
They were invaders, squatters, and mountebanks twice over. Whereas the line of Harold Godwinson of England were only squatters once over, as were the Brythonic Celts Harold's ancestors had rudely displaced.
There wasn't anyone truly indigenous in the entire cast of players.
Except maybe a few dark-haired Pictish remnants in the craggier recesses and deeper bogs around Cape Wrath.