Professor Peterson set out to learn about her African American ancestors in New York in the 19th century. There were not a lot of records kept, but thanks to the heroic efforts of Arthur Schomburg and the archive he created, she found enough to learn some and imagine more.
Slavery ended in New York in 1827, but of course there was still a lot of legal and social oppression. Still, some black people were able to make lives, to find work (they couldn't be doctors, but they could be pharmacists--a profession that was just beginning to be scientific), and to nourish their minds with literature and the arts. Of course they weren't perfect; they were no better than the white people of the time at finding ability among women. Still, it's an inspiring story.