Sam Hall, 47 Years A Slave: A Brief Story of His Life Before and After Freedom Came to Him. Washington, Iowa: Journal Print, 1912. Posted at Documenting the American South. https://docsouth.unc.edu/neh/hall/summary.html.
There are few contemporary accounts of African-American life in Iowa from the late 1800s. This is a great one, written along with Orville Elder--who wrote much of the first sections of the book, so look out for first and third person writing. This is from “Documenting the American South,” a fantastic collection of links from UNC to every surviving slave autobiography. Yes, you read that right: all of them. https://docsouth.unc.edu/neh/hall/summary.html