One of the earliest settlers in Chicago, John Kinzie, illegally held a man as a slave who ultimately ran away. Kinzie then sued him in Louisiana to get him back:
In 1804 John Kinzie moved into the old DuSable cabin on the north bank of the Chicago River and began trading with the local Native tribes. Thomas Forsyth Jr, his half-brother, was in business with him. That spring the partners took on an indentured servant named Jeffrey Nash.
Sometime after the 1804 indenture was instituted, Forsyth took Nash there. And sometime later Nash ran away. He eventually made his way to New Orleans, married, and started a family.
The traders were not about to let Nash go. In 1813 they began proceedings in Louisiana to get him back. The case was labeled Kensy (sic) and Forsyth, plaintiffs v. Jeffrey Nash, defendant.
Now the plaintiffs claimed that Nash was not a free-born servant under indenture, but actually their slave. Residents of Peoria had recognized Nash as Forsyth’s slave. Nash himself was said to have admitted being a slave, and had run away when Forsyth broke a promise to free him. The traders also produced a bill of sale transferring the slave Nash to them, dated September 5, 1803.
However, the Northwest Ordinance of 1787 banned slavery from the territory that would eventually become Ohio, Indiana, Michigan, Illinois, and Wisconsin. The only exceptions were for persons convicted of a crime, or fugitive slaves escaping from a slave-holding state. Nash did not fall under either of these categories. Therefore, the court found in his favor. He would remain a free man.
The road in downtown Chicago named after Kinzie was the locus of the biggest disaster in city history.