Danette Holmes Burnette discovered that her great-great-grandfather, a slave named Cornelius Holmes, was owned by U.S. Congressman Preston Brooks.
The same Preston Brooks who beat a senator unconscious on the floor of the U.S. Senate in 1856 after that senator denounced slavery.Burnette even found an interview with Cornelius among the Slave Narratives on the Library of Congress website.
The incident sparked a national furor, prompting Brooks' resignation and return to office, shortly before the Civil War.
"Dat turn the world upside down," is what Cornelius Holmes told the interviewer of what Preston Brooks did. [Link]