According to the U.S. Census Bureau, the county has a total area of, of which is land and is water. The county is bounded on the north by Sangamon River, and intersected by the south fork of that stream.
In recent years, average temperatures in the county seat of Taylorville have ranged from a low of in January to a high of in July, although a record low of was recorded in January 1994 and a record high of was recorded in August 1988. Average monthly precipitation ranged from in January to in May.
Demographics
As of the 2010 United States Census, there were 34,800 people, 14,055 households, and 9,211 families residing in the county. The population density was. There were 15,563 housing units at an average density of. The racial makeup of the county was 96.6% white, 1.4% black or African American, 0.5% Asian, 0.1% American Indian, 0.4% from other races, and 0.9% from two or more races. Those of Hispanic or Latino origin made up 1.4% of the population. In terms of ancestry, 21.9% were German, 12.7% were Irish, 10.6% were American, and 9.9% were English. Of the 14,055 households, 30.1% had children under the age of 18 living with them, 50.1% were married couplesliving together, 10.3% had a female householder with no husband present, 34.5% were non-families, and 29.9% of all households were made up of individuals. The average household size was 2.36 and the average family size was 2.90. The median age was 41.6 years. The median income for a household in the county was $41,712 and the median income for a family was $52,680. Males had a median income of $42,897 versus $30,027 for females. The per capita income for the county was $21,519. About 12.7% of families and 16.6% of the population were below the poverty line, including 28.6% of those under age 18 and 9.4% of those age 65 or over.
Like most of German-settled Central Illinois, Christian County was solidly Democratic until Woodrow Wilson’s response to German defeat in World War I turned the county over to the Republican Party in its 1920, 1924 and 1928 landslides. The county remained Democratic-leaning through the rest of the twentieth century, only voting Republican in landslide wins. However, since 2000 Christian County has become reliably Republican due to opposition in this rural county to the Democratic Party’s liberal position on social issues.