WARNING: This is a blackface minstrel song, a genre that features demeaning caricatures people rooted in racism and white supremacy.

“Nelly Bly” was submitted for copyright deposit on February 8, 1850, by Firth, Pond & Co. of New York. 

According to Evelyn Foster Mornweck’s The Chronicles of Stephen Foster’s Family:

The subject of Stephen’s happy love song, “Nelly Bly,” also was a real person. When Mary Keller’s sister Rachel married Harry Woods, they lived (until 1855) down on Penn Street, just across the way from Dr. McDowell’s. The Woods’s home, as well as the McDowells’, was a favorite gathering place for the Knights of the S. T. and their musical friends. In later years, the story was told by Mrs. Woods that one evening a party consisting of Stephen, Dick Cowan, Cust Blair, and Marshall Swartzwelder were serenading the Woods family (and incidentally, the McDowells) from the front porch steps. A comely colored girl poked her head out of the cellar door to listen to the music. Stephen observed her and asked Rachel, “Who’s that?” “That’s Nelly Bly,” replied Rachel Woods. The name caught Stephen’s fancy, and when the visitors were invited into the house, he went immediately to the piano, and improvised and played and sang “Nelly Bly” with almost the identical words and music afterward published and sung the world over. The daughter of a former slave, Nelly lived with the Woods family for many years.