This is excellent. My first thought was that it would be perfect for a Radiolab episode, then I noticed that Krulwich wrote it!
THIS WAS AMAZING.
I'd be interested to know more about the claim that, "After the Civil War, a lot of former slaves stayed on this land, and while many migrated North, their families are still there." There's so much that goes into migration patterns and it strikes me as being much more complicated than just "They started there, so they stayed there." Northward migration following (and even leading up to) abolition was obviously a huge factor, but it would follow that the Southern population would have reoriented itself toward cities during the industrial revolution, too. I don't see any obvious reason they would've remained rural. /economic history rant
Adding my friend Quinten, who sent it to me this morning.