Short answers, pulled from the story.
More than 42 percent of New York City households held enslaved people in bondage in 1703. This figure stood second only to Charleston, South Carolina where the proportion was even higher.
By 1804 every Northern state had passed laws outlawing slavery either immediately or over time. New York freed its last enslaved people on the 5th of July 1827 and Pennsylvania abolished slavery gradually starting in 1780.
Nat Turner organized a rebellion in Southampton County Virginia during 1831 claiming spiritual visions and killing nearly sixty white inhabitants. Militia forces captured Turner along with seventeen other rebels who were subsequently hanged.
Southern leaders claimed global economies depended heavily on cotton exports affordable only through enslaved labor. They argued civilized societies required one portion living off another's labor so learning science arts could flourish.
The Thirteenth Amendment was ratified the 6th of December 1865 prohibiting slavery involuntary servitude except punishment crime. Before Reconstruction ended 1877 many economic social functions continued through segregation sharecropping convict leasing.