Warren County was organized in 1825 out of Pike County which consisted of all portions of the state north and west of the Illinois River before 1825. Henderson County was formed in 1841 from the western area of Warren County. Warren County was named for Dr. Joseph Warren, killed at the Battle of Bunker Hill in 1775. He is believed to have been the first officer to die in the Revolutionary War. The current courthouse, constructed of red Portage stone, was completed in 1895.
Geography
According to the U.S. Census Bureau, the county has a total area of, of which is land and is water.
Climate and weather
In recent years, average temperatures in the county seat of Monmouth have ranged from a low of in January to a high of in July, although a record low of was recorded in February 1905 and a record high of was recorded in July 1936. Average monthly precipitation ranged from in January to in July.
At the 2010 United States Census, there were 17,707 people, 6,918 households and 4,617 families residing in the county. The population density was. There were 7,682 housing units at an average density of. The racial makeup of the county was 91.3% white, 1.7% black or African American, 0.5% Asian, 0.2% American Indian, 0.1% Pacific islander, 4.5% from other races, and 1.6% from two or more races. Those of Hispanic or Latino origin made up 8.4% of the population. In terms of ancestry, 25.2% were German, 14.7% were Irish, 11.3% were English, 10.0% were Swedish, and 5.5% were American. Of the 6,918 households, 29.6% had children under the age of 18 living with them, 52.2% were married couplesliving together, 9.7% had a female householder with no husband present, 33.3% were non-families, and 28.2% of all households were made up of individuals. The average household size was 2.40 and the average family size was 2.91. The median age was 39.6 years. The median household income was $41,636 and the median family income was $49,623. Males had a median income of $40,289 and females $25,460. The per capita incomewas $20,047. About 11.0% of families and 13.4% of the population were below the poverty line, including 18.1% of those under age 18 and 10.6% of those age 65 or over.
Politics
Warren County is located in Illinois's 17th Congressional District and is currently represented by Democrat Cheri Bustos. For the Illinois House of Representatives, the county is split between the 93rd district, currently represented by Republican Norine Hammond, and the 94th district, currently represented by Randy Frese. The county is located in the 47th district of the Illinois Senate, and is currently represented by Republican Jil Tracy. In presidential elections, Warren County voted for the Republican Party's candidate in every election from 1936 through 1988, often by a wide margin. From 1992–2012, the contest in Warren County was more competitive, with the Democratic Party's candidate winning four out of six times.
In a scene in the 2018 film "Halloween", the local sheriff drives a car that says Warren County Sheriff's Department. Confirming that the fictional town of Haddonfield is located in Warren County.
