Another bit about civil war revisionism, it is definitely true that the war was brought on by economic and cultural differences between the North and the South, but those differences were themselves brought on by slavery (or at the very least, the plantation economy, but slavery was foundational to that).
Slavery breeds what are called "extractive" institutions, whereby the government starts to get in its head that its job is to accumulate wealth rather than to improve the state or the people's condition. Extractive institutions warp both culture and economics.
Although some of the South's cultural differences are because different groups of Englishmen settled there predominantly. South was mostly Borderers (folks from around Hadrian's Wall) and Restoration-era Cavaliers. North had more Quakers and Puritans, though both groups settled in both places. But slavery cemented those differences and is why Dixie only slowly recovered (and places right in the heart of Dixie, like Mississippi, Alabama, and Arkansas, never recovered their former economic clout). Only places northerners migrated to like Florida, Texas, North Carolina, Virginia, and Georgia became economic powerhouses anew.
