McLeansboro is a city in Hamilton County, Illinois, United States. The population was 2,883 at the 2010 census. The estimated population as of 2016 was 2,743. It is the county seat of Hamilton County.McLeansboro is part of the Mount Vernon, Illinois micropolitan area.GeographyMcLeansboro is located at .According to the 2010 census, McLeansboro has a total area of 2.741sqmi, of which 2.61sqmi is land and 0.131sqmi is water.HistoryThe city was named for Dr. William McLean, an early settler.DemographicsAs of the census of 2000, there were 2,945 people, 1,265 households, and 747 families residing in the city. The population density was 1,286.3 people per square mile (496.5/km²). There were 1,444 housing units at an average density of 630.7/sq mi (243.5/km²). The racial makeup of the city was 98.10% White, 0.78% African American, 0.03% Native American, 0.20% Asian, 0.03% Pacific Islander, 0.17% from other races, and 0.68% from two or more races. Hispanic or Latino of any race were 0.37% of the population.
