Two historic sites in Hanover Township are listed on the National Register of Historic Places: the David Littell House, a nineteenth-century farmhouse, and the Recreational Demonstration Area part of Raccoon Creek State Park, which was built by the Civilian Conservation Corps during the Great Depression.
According to the United States Census Bureau, the township has a total area of 45.0 square miles (117 km2), of which, 44.9 square miles (116 km2) of it is land and 0.2 square miles (0.52 km2) of it (0.36%) is water.
As of the census of 2000, there were 3,529 people, 1,288 households, and 1,025 families residing in the township. The population density was 78.7 people per square mile (30.4/km²). There were 1,413 housing units at an average density of 31.5/sq mi (12.2/km²). The racial makeup of the township was 98.30% White, 0.60% African American, 0.20% Native American, 0.14% Asian, 0.20% from other races, and 0.57% from two or more races. Hispanic or Latino of any race were 0.99% of the population.
There were 1,288 households out of which 35.5% had children under the age of 18 living with them, 70.0% were married couples living together, 6.7% had a female householder with no husband present, and 20.4% were non-families. 17.9% of all households were made up of individuals and 6.8% had someone living alone who was 65 years of age or older. The average household size was 2.74 and the average family size was 3.11.
In the township the population was spread out with 25.6% under the age of 18, 7.2% from 18 to 24, 30.5% from 25 to 44, 26.6% from 45 to 64, and 10.1% who were 65 years of age or older. The median age was 38 years. For every 100 females there were 100.9 males. For every 100 females age 18 and over, there were 99.8 males.
The median income for a household in the township was $44,393, and the median income for a family was $51,000. Males had a median income of $40,544 versus $24,770 for females. The per capita income for the township was $18,079. About 2.5% of families and 3.7% of the population were below the poverty line, including 5.8% of those under age 18 and 3.1% of those age 65 or over.
- ^ Schmidlapp, Christina. National Register of Historic Places Inventory/Nomination: David Littell House. National Park Service, 1986-07-11. Accessed 2009-10-29.
- ^ Milner, John, Associates. National Register of Historic Places Inventory/Nomination: Raccoon Creek RDA. National Park Service, October 1986. Accessed 2009-12-17.
- ^ “American FactFinder”. United States Census Bureau. http://factfinder.census.gov. Retrieved 2008-01-31.