The current courthouse, constructed of red Portage stone, was completed in 1895.

[5] At the 2010 United States census, there were 17,707 people, 6,918 households and 4,617 families residing in the county.

[14] Warren County is located in Illinois's 17th Congressional District and is currently represented by Democrat Cheri Bustos.

The county is located in the 47th district of the Illinois Senate, and is currently represented by Republican Jil Tracy.

From 1992 to 2012, the contest in Warren County was more competitive, with the Democratic Party's candidate winning four out of six times.

Confirming that the fictional town of Haddonfield is located in Warren County.