The Clays were an influential nineteenth-century U.S. political and business dynasty.
The Clays are of English stock, and there are quite a few Clay families still in England, and also in other parts of the world.
[1][self-published source] Henry Clay, Jr. owned an enslaved man named John Henry Clay among whose 20th century descendants were the boxer Muhammad Ali and his father, Cassius Marcellus Clay, Sr.: