Irwinton, the county seat of Wilkinson County, was incorporated December 4, 1816. Although the city is named for Georgia governor Jared Irwin, Irwinton was originally known as Bethel, then later as High Hill Fraction.

The county courthouse is said to be on the grounds of an early Indian trading post. During the Civil War, Irwinton was one of the cities Sherman destroyed and burned, including the county courthouse. The present courthouse dates back to 1924.