Some of the best if not the very best craftsmen were black. Coach builders, Cabinet Makers and Furniture makers such as Thomas Day, Masons, plasterers, house builders, blacksmiths. The blacks in the South were some of the best artisans the world had ever seen. They were able to practice these trades in the South, whereas laws were passed in nearly all states in the North banning blacks from engaging in any trades. There was no living to be carved or etched out in the North at all. Ohio, New Jersey, Illinois, Washington and many other states in the North even outright banned blacks from entering the state and made it a crime if they remained which resulted in imprisonment and then expulsion. Blacks had no interest in going to the North and they never bothered to travel north as the racial dot map historically shows as wells as first hand historical accounts prove. Blacks could not make any kind of living at all in the North, nor could they own any property.
Blacks in the South owned some of the largest plantation houses pre-civil war. The largest slaveholder in NC at one time was a black man, John Carruthers Stanly. There were no blacks of any wealth or means in the North at all as they were barred from obtaining anything.