William Cabell Rives (1793-1868) was a Virginian who studied law with Thomas Jefferson before serving in congress alongside MVB as a member of the U.S. House of Representatives from 1823 to 1829 as a member of the Democratic party. From 1829 to 1832 Rives served as the American Minister to France and corresponded closely with MVB regarding Rives' successful attempts to get France to pay debts due to Americans dating back to the Quasi War. He later served in the U.S. Senate from 1832 to 1834 and again from 1841 to 1845 as a member of the Whig party.
"William Cabell Rives," Biographical Directory of the United States Congress, accessed March 18, 2021, http://bioguide.congress.gov/scripts/biodisplay.pl?index=r000285, "William Cabell Rives," findagrave.com, accessed March 18, 2021, https://www.findagrave.com/memorial/10353022/william-cabell-rives