September 30, 1836
Benton County was formally established as a separate county from Washington County. Located in the northwest corner of Arkansas, Benton County borders Missouri and Oklahoma and is part of the Ozark Plateau. It was named in honor of U.S. senator Thomas Hart Benton of Missouri, who had played a key role in Arkansas’s admission into the Union. The county seat, Bentonville, was also named after Sen. Benton.