Warsaw, the seat of Gallatin county, is located on the Ohio River. The area was settled around 1800 and was first known as Ohio River Landing. The town was established as Fredericksburg in 1814, named for Adolphus Frederick, a local boat builder. It was renamed Warsaw in 1831 to avoid confusion with the Washington county town of Fredericktown. The name Warsaw came from Thaddeus of Warsaw by Jane Porter. Warsaw became the county seat in 1838 when Carroll county was formed from Gallatin county. Until that time the county seat had been Port William, which was renamed Carrollton in 1838. The Fredericksburg post office operated from 1816 until 1831 when it was renamed Warsaw. The population in 1990 was 1,202.