Black Dog: I understand you completely about the rightwards shift of the Labour Party, however, I think it is significant that it is not simply the South East exercised some tyrannical control over the whole nation. Ultimately people like Gordon Brown and Tony Blair were still elected by their Scottish constituents, not by the Southern upper-middle class (who in fact didn't vote for New Labour, even if the landslide of 1997 there were still 165 Tory seats in England). There is a great amount of London-centrism (even here in East Anglia it's a joke that the government can't see past the Watford gap, let alone all the way up North) but I don't think it has anything to do with the people of the South East, it's the fault of the entire country for being so stupid as for people in places like Sedgefield to vote for smiling creeps like Tony Blair (whatever you think about the man's politics, you must agree his smile is unnerving). Ultimately, it is the work of a British elite, that happen to reside mainly in London, not some sort of South Eastern oligarchy (I mean if that was the case, at least some people in this country would be happy).
Likewise you mention how Scotland etc. don't see themselves as regions and want to fight the centre-right. So why in the national elections do they consistently keep voting for New Labour and propping it up? If not for previous industrial areas being so short-sighted as to just think red=good when voting then New Labour would never have been possible - it relied as much on safe areas dumbly voting for them as it did on "middle-class" areas swinging to them. We might as well have a series of regional assemblies if it is a case of feeling disenfranchised (which people have effectively done for themselves) as in Germany or the USA, I see no reason why they should be restricted to just Wales and Scotland.
Back to the OP: in regards to looking at Holland, could the Protestant work ethic have anything to do with the high populations in both these areas?