|Cass County, Illinois|
Location in the U.S. state of Illinois
Illinois's location in the U.S.
|Named for||Lewis Cass|
|• Total||384 sq mi (995 km2)|
|• Land||376 sq mi (974 km2)|
|• Water||7.9 sq mi (20 km2), 2.1%|
|• ( 2010)||13,642|
|• Density||36/sq mi (14/km2)|
|Time zone||Central: UTC−6/ −5|
Cass County is a county located in the U.S. state of Illinois. As of the 2010 census, the population was 13,642.  Its county seat is Virginia.  It is the home of the Jim Edgar Panther Creek State Fish and Wildlife Area.
Cass County was formed in 1837 out of Morgan County. It was named in honor of Lewis Cass,  a general in the War of 1812, Governor of the Michigan Territory, and United States Secretary of State in 1860. Cass was serving as Andrew Jackson's Secretary of War just before the County was named.
- Mason County - northeast
- Menard County - east
- Sangamon County - southeast
- Morgan County - south
- Brown County - west
- Schuyler County - northwest
|Climate chart ( explanation)|
In recent years, average temperatures in the county seat of Virginia have ranged from a low of 15 °F (−9 °C) in January to a high of 87 °F (31 °C) in July, although a record low of −28 °F (−33 °C) was recorded in February 1934 and a record high of 114 °F (46 °C) was recorded in July 1954. Average monthly precipitation ranged from 1.35 inches (34 mm) in January to 4.86 inches (123 mm) in May. 
|U.S. Decennial Census
1790-1960  1900-1990 
1990-2000  2010-2013 
As of the 2010 United States Census, there were 13,642 people, 5,270 households, and 3,561 families residing in the county.  The population density was 36.3 inhabitants per square mile (14.0/km2). There were 5,836 housing units at an average density of 15.5 per square mile (6.0/km2).  The racial makeup of the county was 86.3% white, 3.1% black or African American, 0.3% Asian, 0.3% American Indian, 8.7% from other races, and 1.4% from two or more races. Those of Hispanic or Latino origin made up 16.8% of the population.  In terms of ancestry, 22.6% were German, 21.0% were American, 10.6% were Irish, and 9.5% were English. 
Of the 5,270 households, 33.9% had children under the age of 18 living with them, 51.1% were married couples living together, 10.9% had a female householder with no husband present, 32.4% were non-families, and 26.5% of all households were made up of individuals. The average household size was 2.55 and the average family size was 3.06. The median age was 38.7 years. 
The median income for a household in the county was $41,544 and the median income for a family was $51,624. Males had a median income of $37,267 versus $26,634 for females. The per capita income for the county was $19,825. About 10.1% of families and 12.9% of the population were below the poverty line, including 14.2% of those under age 18 and 9.2% of those age 65 or over. 
Typically for German-settled western Central Illinois, Cass County opposed the Civil War and became solidly Democratic for the next six decades. Only hatred of Woodrow Wilson’s policies towards Germany following World War I drove the county into Republican hands in the 1920 landslide. Between 1924 and 2008, the county was something of a bellwether, missing the national winner only in the very close 1960 election and the heavily drought- and farm crisis-influenced election of 1988. In the 2010s, the county has become powerfully Republican due to opposition to the Democratic Party’s social liberalism.
Cass County is located in Illinois's 18th Congressional District and is currently represented by Republican Davin LaHood. For the Illinois House of Representatives, the county is located in the 93rd district and is currently represented by Republican Norine Hammond. The county is located in the 47th district of the Illinois Senate, and is currently represented by Republican Jil Tracy.
- A C Central Community Unit School District 262
- Beardstown Community Unit School District 15
- Porta Community Unit School District 202
- Triopia Community Unit School District 27
- Virginia Community Unit School District 64
Cass County is divided into these eleven townships:
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