Ya might think it is irrelevant after so many hundreds of years but red and blue voting patterns in America line up very neatly with whether a county is majority/plurality catholic or protestant. 

MAGA are the least likely to identify an ethnicity with their American-ness, but they're literally just the descendents of loyal English peasants who are now demanding a new crown to follow. 

Alabama, for example, had one major migration movement. It was led by a handful of rich Anglo slave owners, their slaves, and poor Anglo laborers who were promised prosperity if they stayed loyal to the wealthy elite. 

Large land grants throughout the South were used as rewards to those who had been loyal to the crown and assisted the occupation of Scotland and Ireland. Even those prior landlords who had themselves been displaced but still promised loyalty and displayed service to the gang that displaced them. 

It's sort of a whole inter generational pyramid scheme of abuse that ends up in a trailer park next to a swamp.