Knox County was named in honor of Henry Knox, the first US Secretary of War. The first "Knox County" in what today is Illinois was unrelated to the modern incarnation. In 1790, the land of the Indiana Territory that was to become Illinois was divided into two counties: St. Clair and Knox. The latter included land in what was to become Indiana. When Knox County, Indiana, was formed from this portion of the county in 1809, the Illinois portions were subdivided into counties that were given other names. The modern Knox County, Illinois, was organized in 1825, from Fulton County, itself a portion of the original St. Clair County. Like its neighbor to the south, Fulton County, for its Spoon River Drive, Knox County is also known for a similar scenic drive fall festival the first two weekends in October, the Knox County Drive.
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 Galesburg have ranged from a low of in January to a high of in July, although a record low of was recorded in January 1982 and a record high of was recorded in July 1983. Average monthly precipitation ranged from in January to in July.
As of the 2010 United States Census, there were 52,919 people, 21,535 households, and 13,324 families residing in the county. The population density was. There were 24,077 housing units at an average density of. The racial makeup of the county was 87.5% white, 7.2% black or African American, 0.6% Asian, 0.2% American Indian, 1.9% from other races, and 2.5% from two or more races. Those of Hispanic or Latino origin made up 4.8% of the population. In terms of ancestry, 23.1% were German, 14.9% were Irish, 11.7% were English, 11.6% were Swedish, and 8.0% were American. Of the 21,535 households, 27.2% had children under the age of 18 living with them, 45.7% were married couples living together, 11.9% had a female householder with no husband present, 38.1% were non-families, and 32.3% of all households were made up of individuals. The average household size was 2.27 and the average family size was 2.84. The median age was 42.0 years. The median income for a household in the county was $39,545 and the median income for a family was $51,740. Males had a median income of $42,067 versus $25,380 for females. The per capita income for the county was $20,908. About 10.9% of families and 15.5% of the population were below the poverty line, including 24.7% of those under age 18 and 7.3% of those age 65 or over.
Knox County's political history is typical of Yankee-settled Northern Illinois. It leaned Whig during its early elections – although giving a plurality to Franklin Pierce in 1852 – and become powerfully Republican following that party's formation. Although Knox did support ProgressiveTheodore Roosevelt against conservative incumbent President William Howard Taft in 1912, it was Franklin D. Roosevelt’s 1932 landslide before Knox County again gave the Democratic Party so much as a plurality, and it did not give a Democratic absolute majority until Lyndon B. Johnson gained such against the anti-Yankee, Southern-leaning Barry Goldwater in 1964. Since then, Knox County gradually trended Democratic for the following four decades, so that Michael Dukakis in his losing 1988 campaign was to carry the county by the same margin as Johnson had done in 1964. During the 1990s and 2000s, Knox was a solidly Democratic county, voting Democratic by at least nine percentage points in every election from 1992 to 2012. The 2016 election, in the shadow of high unemployment in the “Rust Belt” saw a swing of over twenty percentage points to Donald Trump, who became the first Republican victor in the county since Ronald Reagan in 1984 when he came within 3,819 votes of cleansweeping all fifty states.
