Carrollton is a town in Carroll County, Kentucky, at the confluence of the Ohio River and the Kentucky River. Its population was 3,846 at the 2000 census. It is the county seat of Carroll County. Carrollton was founded in 1794, and it was known as Port William initially. It served as the county seat of Gallatin County until 1838 when the county was split, creating Carroll County, and Port William was renamed Carrollton and became the seat of the new county. The Louisville & Nashville Railroad was built near town in 1868 and eventually became more important to the town's economy than river traffic. It has one of the state's largest tobacco markets, and the population has remained steady since being recorded at 3,884 in the 1970 census. See Carrollton bus disaster for an important, and tragic, event in Carroll County's history.