Barbourville, the seat of Knox county, was established in 1800 on land given by James Barbour for the purpose. The area had been explored in 1750 by Dr. Thomas Walker and Richard Ballinger opened a tavern nearby on the Wilderness Road about 1795. The Barbourville post office opened in 1804. The population in 1990 was 3,658.
The Knox County Courthouse in Barbourville, the fifth, was built in 1964.
Barbourville is the home of Union College.