DeKalb County, Illinois

DeKalb County
DeKalb County's Legislative Center
DeKalb County's Legislative Center
Official seal of DeKalb County
Map of Illinois highlighting DeKalb County
Location within the U.S. state of Illinois
Map of the United States highlighting Illinois
Illinois's location within the U.S.
Coordinates: 41°53′N 88°46′W / 41.89°N 88.77°W / 41.89; -88.77
Country  United States
State  Illinois
Founded 4 March 1837
Named for Johann de Kalb
Seat Sycamore
Largest city DeKalb
 • Total 635 sq mi (1,640 km2)
 • Land 631 sq mi (1,630 km2)
 • Water 3.4 sq mi (9 km2)  0.5%
 ( 2010)
 • Total 105,160
 • Estimate 
 • Density 170/sq mi (64/km2)
Time zone UTC−6 (Central)
 • Summer (DST) UTC−5 (CDT)
Congressional districts 14th, 16th

DeKalb County is a county located in the U.S. state of Illinois. As of the 2010 United States Census, the population was 105,160.[1] Its county seat is Sycamore.[2]

DeKalb County is part of the Chicago-Naperville-Elgin, IL-IN-WI Metropolitan Statistical Area.


DeKalb County was formed on 4 March 1837,[3] out of Kane County, Illinois. The County was named for Johann de Kalb,[4] a German (Bavarian) hero of the American Revolutionary War. DeKalb County's area is approximately 632.7 square miles, located 63 miles west of Chicago. There are 19 townships in the county with the county seat at Sycamore.

Between 1834 and 1837, white men began to settle in DeKalb County along the streams and wooded areas because of the fertile soil, wild game, and food and water opportunities. Major growth stemmed from the introduction of the railroad which brought easier methods of transportation and opportunities for industrial growth. Early industries based in DeKalb County included Sandwich Mfg. Co, Marsh Harvester Co, Barbed Wire, and Gurler Bros Pure Milk Co.

The county is noted for agriculture. In 1852, the DeKalb Agricultural Society produced the county's first Agricultural Fair, in Sycamore. Eventually farmers, businessmen, bankers and newspapermen organized to become the DeKalb County Soil Improvement Association, which later was split into DeKalb County Farm Bureau and DeKalb Agricultural Association (DEKALB AgResearch, Inc., Monsanto). DeKalb County is credited with being the birthplace of the Farm Bureau movement. DeKalb County is also the 2nd largest hog producing county in Illinois and the 66th largest in the nation.

Education has played an important role in the area with Northern Illinois University located in DeKalb and Kishwaukee Community College located in Malta. A major fair has been held each year since 1887 at the Sandwich Fairgrounds in Sandwich.


Unlike similarly spelled locations, such as DeKalb County, Georgia, DeKalb denizens from Illinois pronounce the county name /dɪˈkælb/ di-KALB, with an L sound, as in German.


According to the US Census Bureau, the county has a total area of 635 square miles (1,640 km2), of which 631 square miles (1,630 km2) is land and 3.4 square miles (8.8 km2) (0.5%) is water.[5]

Climate and weather

Sycamore, Illinois
Climate chart (explanation)
Average max. and min. temperatures in °F
Precipitation totals in inches
Source: The Weather Channel[6]

In recent years, average temperatures in the county seat of Sycamore have ranged from a low of 10 °F (−12 °C) in January to a high of 84 °F (29 °C) in July, although a record low of −27 °F (−33 °C) was recorded in January 1985 and a record high of 103 °F (39 °C) was recorded in August 1988. Average monthly precipitation ranged from 1.40 inches (36 mm) in February to 4.49 inches (114 mm) in June.[6]

Adjacent counties

Major highways


As of the 2010 United States Census, there were 105,160 people, 38,484 households, and 23,781 families residing in the county.[12] The population density was 166.6 inhabitants per square mile (64.3/km2). There were 41,079 housing units at an average density of 65.1 per square mile (25.1/km2).[5] The racial makeup of the county was 85.1% white, 6.4% black or African American, 2.3% Asian, 0.3% American Indian, 3.9% from other races, and 2.0% from two or more races. Those of Hispanic or Latino origin made up 10.1% of the population.[12] In terms of ancestry, 32.6% were German, 17.5% were Irish, 8.7% were English, 7.0% were Polish, 6.4% were Italian, 6.3% were Swedish, and 3.8% were American.[13]

Of the 38,484 households, 31.9% had children under the age of 18 living with them, 47.2% were married couples living together, 10.2% had a female householder with no husband present, 38.2% were non-families, and 25.8% of all households were made up of individuals. The average household size was 2.56 and the average family size was 3.11. The median age was 29.3 years.[12]

The median income for a household in the county was $54,002 and the median income for a family was $70,713. Males had a median income of $50,192 versus $35,246 for females. The per capita income for the county was $24,179. About 7.7% of families and 14.6% of the population were below the poverty line, including 13.2% of those under age 18 and 4.5% of those age 65 or over.[14]







As part of Northern Illinois, DeKalb County was a stronghold for the Free Soil Party in its early elections – being among nine Illinois counties to support Martin Van Buren in 1848 – and became overwhelmingly Republican for the century following that party's formation. The only time it did not back the official GOP nominee between 1856 and 1988 was in 1912 when the Republican Party was mortally divided and Progressive Theodore Roosevelt won almost half the county's vote. Republican candidate Alf Landon, who lost 46 of 48 states in 1936, won DeKalb County by double digits, whilst even Barry Goldwater – renowned for his antagonism towards the establishment – won by seven percent despite losing sixteen percent of the vote compared to Richard Nixon in 1960.

Beginning in 1992, DeKalb County has shown a strong trend towards the Democratic Party owing to the growth of its powerfully Democratic student population. In that year's election George McGovern, who was to lose all but 130 counties nationwide, managed to exceed his nationwide vote percentage in this county that had not voted Democratic since giving a plurality to Franklin Pierce in 1852. In 1980, Illinois native John B. Anderson won over fifteen percent of the county's vote and this was to shift towards the Democratic Party in subsequent elections. In 1992 and 1996, Bill Clinton became the first Democrat to carry the county in 140 years, and in 2008 another Illinois son, Barack Obama, became the first Democrat to win an absolute majority since Van Buren in the county's first-ever Presidential election of 1840. Obama repeated this in 2012, but economic concerns in the rust belt caused a sizeable swing away from Hillary Clinton in 2016, although she still narrowly won the county.

See also


  1. ^ a b "State & County QuickFacts". US Census Bureau. Archived from the original on June 6, 2011. Retrieved July 4, 2014.
  2. ^ "Find a County". National Association of Counties. Archived from the original on May 31, 2011. Retrieved June 7, 2011.
  3. ^ Illinois Regional Archives Depository System. "Name Index to Illinois Local Governments". Illinois State Archives. Illinois Secretary of State. Retrieved August 30, 2013.
  4. ^ Gannett, Henry (1905). The Origin of Certain Place Names in the United States. Govt. Print. Off. p. 103.
  5. ^ a b "Population, Housing Units, Area, and Density: 2010 - County". US Census Bureau. Retrieved July 11, 2015.
  6. ^ a b "Monthly Averages for Sycamore IL". The Weather Channel. Retrieved January 27, 2011.
  7. ^ "Population and Housing Unit Estimates". Retrieved November 6, 2019.
  8. ^ "US Decennial Census". US Census Bureau. Archived from the original on April 26, 2015. Retrieved July 4, 2014.
  9. ^ "Historical Census Browser". University of Virginia Library. Retrieved July 4, 2014.
  10. ^ "Population of Counties by Decennial Census: 1900 to 1990". US Census Bureau. Retrieved July 4, 2014.
  11. ^ "Census 2000 PHC-T-4. Ranking Tables for Counties: 1990 and 2000" (PDF). US Census Bureau. Retrieved July 4, 2014.
  12. ^ a b c "Profile of General Population and Housing Characteristics: 2010 Demographic Profile Data". US Census Bureau. Retrieved July 11, 2015.
  13. ^ "Selected Social Characteristics in the United States – 2006-2010 American Community Survey 5-Year Estimates". US Census Bureau. Retrieved July 11, 2015.
  14. ^ "Selected Economic Characteristics – 2006-2010 American Community Survey 5-Year Estimates". US Census Bureau. Retrieved July 11, 2015.
  15. ^ Leip, David. "Atlas of US Presidential Elections". Retrieved November 1, 2018.


Further reading

External links

Coordinates: 41°53′37″N 88°46′13″W / 41.89361°N 88.77028°W / 41.89361; -88.77028