St. Leon is a town in Kelso Township, Dearborn County, Indiana, United States. The population was 678 at the 2010 census. It is also home to a wiffleball tournament, Wifflerama. History A post office was established at St. Leon in 1852, and remained in operation until it was discontinued in 1955. The town was likely named for St. Leon Bembo. Geography St. Leon is located at (39.287360, -84.967108). According to the 2010 census, St. Leon has a total area of , of which (or 99.87%) is land and (or 0.13%) is water. Demographics 2010 census As of the census of 2010, there were 678 people, 252 households, and 182 families living in the town. The population density was . There were 263 housing units at an average density of . The racial makeup of the town was 98.1% White, 0.1% African American, 0.6% Asian, 0.4% from other races, and 0.7% from two or more races. Hispanic or Latino of any race were 0.3% of the population. There were 252 households, of which 36.5% had children under the age of 18 living with them, 59.1% were married couples living together, 9.5% had a female householder with no husband present, 3.6% had a male householder with no wife present, and 27.8% were non-families. 24.2% of all households were made up of individuals, and 9.9% had someone living alone who was 65 years of age or older. The average household size was 2.69 and the average family size was 3.23. The median age in the town was 36.2 years. 26.8% of residents were under the age of 18; 9% were between the ages of 18 and 24; 24.9% were from 25 to 44; 26.2% were from 45 to 64; and 13.1% were 65 years of age or older. The gender makeup of the town was 50.0% male and 50.0% female. 2000 census As of the census of 2000, there were 387 people, 133 households, and 109 families living in the town. The population density was . There were 139 housing units at an average density of 19.4 per square mile (7.5/km). The racial makeup of the town was 99.74% White and 0.26% Asian. There were 133 households, out of which 35.3% had children under the age of 18 living with them, 74.4% were married couples living together, 6.0% had a female householder with no husband present, and 17.3% were non-families. 15.8% of all