[bcmo]

I never thought it had its basis in genetics, though that is pretty interesting. At least from what I remember in reading Albion's seeds it was the result of distinct cultures.

I think the division can be pretty broad. I live in Boston, and I've sometimes heard comparisons of North Shore vs South Shore to be culturally rooted in Puritans settling North, vs Pilgrims settling in South. Generally genetically the same but a little different starting point, culturally.

[iguy]

There's no conflict here. In a world where people were perfectly blank slates, and all such patterns were purely culturally transmitted, you would still expect a giant Yankee blob on the map just because they mostly came from East Anglia. (And the people of England when they left weren't perfectly mixed, most had lived in one region for millennia.)