Didn't this guy start the KKK?
In truth, no, but popular culture often credits him as having done so. Before the war, he was a slave trader, plantation owner, and one of the richest men in the South. As a Confederate general, he had successful campaigns in Tennessee and Mississippi, and he was very well respected by most Southerners. After the war, the group that met in Nashville to form what would become the KKK declared him their "Commander in Chief and Grand Dragon" as sort of a rallying point, despite his lack of personal involvement with the group. When later questioned about it, he stated that while he did sympathize with their cause, he was not actually affiliated with the organization. A reconstruction-era congressional investigation into the KKK and their activities in 1871 concluded the same.
Still, to the average man on the street, "Nathan Bedford Forrest started the KKK", which is why I think it's
awesome that has been nominated as the "Greatest American that ever lived"!