I know that in Tulsa, OK, back in the XIX Century, there was a reasonably large African American community that was particularly wealthy and studious.
The folks there were so entrepreneurial they had their own Black Wall Street.
Eventually the racist wave that swept the US during the Nadir ended all of that in what is, to this day, the only aerial bombardment carried out within the borders of the continental US: Hordes of white uncontrollable Tulsans took to the streets to demand the African American population to leave the town immediately (which was common in those days, that's why a large part of blacks in the US now live in urban areas). Although Black folks put up a fight at first, they were quickly reduced by aerial bombardments aided by the local "authorities," members of the police and, of course, the KKK.