There are still French-speaking North American communities identified with certain locales in eastern Canada and, to a lesser extent, Louisiana. No such places exist for Swedish or Russian speakers,. etc., so I don't think the analogy holds up.
I kinda like your ideas "Redneck America," etc., but it would be hard to draw strict geographic boundaries. Actually, there's a lot of overlap
Here in South Louisiana, we are "in the South but not of it." The same is true, in a different way, for South Florida.