Maternally, it's a different picture. Celtic from Scotland and Ireland, Palatines from the Rhineland, Alsace and Switzerland, native Cherokee and Creek going all the way back to James Cittie, French Huguenot and other fleeing outcasts to wild, nearly ungoverned NC from old Virginny, just your usual southern mutt heritage and all that comes with it, good and not so good.
I do perceive "redneck" as being more Celt. Looking back to even England, the "crackers" were from Celt lands, Cornwall and such.
There are those, especially in Ireland, who view our Civil War as the inevitable, repeated clash between Celts and Anglo-Saxons, that has played out throughout the history of the British Isles... past as prologue.
Ironically, while Celtic Southern nationalists insist on being identified with a particularly "reactionary" form of rightism, Celtic nationalists in the British Isles (and Brittany and Galicia as well) have adopted left wing nationalism as their ideology, leaving English nationalism with the "onus" of being "right wing."
If our Southern nationalists had any sense they'd adopt left wing nationalism as well. I mean, at the very least, they'd tie the Left up in knots. But know, they have to stick with the stereotype (and reinforce it here and there).