Randolph County is a county in the northern portion of the U.S. state of Missouri. As of the 2020 census, the population was 24,716. Its county seat is Huntsville. The county was organized January 22, 1829, and named for U.S. Representative and U.S. Senator John Randolph of Roanoke, Virginia.

John Randolph, commonly known as John Randolph of Roanoke, was an American planter, and a politician from Virginia, serving in the House of Representatives at various times between 1799 and 1833, and the Senate from 1825 to 1827. He was also Minister to Russia under Andrew Jackson in 1830. After serving as President Thomas Jefferson's spokesman in the House, he broke with the president in 1805 as a result of what he saw as the dilution of traditional Jeffersonian principles as well as perceived mistreatment during the impeachment of Samuel Chase, in which Randolph served as chief prosecutor. Following this split, Randolph proclaimed himself the leader of the "Old Republicans" or "Tertium Quids", a wing of the Democratic-Republican Party who wanted to restrict the role of the federal government. Specifically, Randolph promoted the Principles of '98, which said that individual states could judge the constitutionality of central government laws and decrees, and could refuse to enforce laws deemed unconstitutional.