It was in the 20th century that national sovereignty really ruled the roost, and the E.U. was formed to cure that.

Traditionally, historians thought in terms of invasions: the Celts took over the islands, then the Romans, then the Anglo-Saxons. It now seems much more likely that the resident population doesn't change as much as thought. The people stay put but are reculturalized by some new dominant culture.

So long as classical education and classical prejudices prevailed, educated Englishmen inevitably saw ancient Britain as an alien land.

Norman Davies Quotes