Illinois Regional Archives Depository (IRAD) System Illinois State Archives
IRAD Home • Administrative Histories / Record Descriptions • Local Government Records Database • Quick Links • Regional Map and Contact Information • Research Policy
McHenry County
Contact InformationMcHenry County Government Center
2200 N. Seminary Ave.
Woodstock, IL 60098
815-334-4242 – County Clerk
815-334-4310 – Circuit Clerk
815-334-4110 – Recorder
IRAD Depository
Founders Memorial Library
Rm. 245B
Northern Illinois University
DeKalb, IL 60115
815-753-1807
Established
- January 16, 1836 (Laws, 1836, p. 273)
Origin of the name of the county
- Named for William McHenry, a pioneer of White County, soldier of the War of 1812 and the Black Hawk War, Representative in the first, fourth, fifth and ninth General Assemblies, and Senator in the sixth General Assembly.
Present area, or parts of it, formerly included in
- 1831–1836 – Cook
- 1831–1836 – LaSalle
- 1825–1831 – Putnam
- 1823–1825 – Fulton
- 1821–1823 – Pike
- 1819–1821 – Clark
- 1816–1819 – Crawford
- 1815–1816 – Edwards
- 1812–1815 – Madison
- 1801–1812 – St. Clair
- 1795–1801 – Knox, Northwest Territory
County Seats
- 1837–1843 – McHenry
- 1843–present – Woodstock (Named Centreville until 1844.)
History of county governing board
- 1836–1850 – County Commissioners’ Court
- 1850–present – County Board of Supervisors
Township Government
- Adopted – November 6, 1849
Township Names
- Alden
- Algonquin
- Burton – Name changed from Benton on December 28, 1850.
- Chemung
- Coral
- Dorr – Name changed from Centre on December 28, 1850.
- Dunham – Name changed from Byron on December 28, 1850.
- Grafton
- Greenwood
- Hartland
- Hebron
- McHenry
- Marengo
- Nunda – Name changed from Brooklyn on December 28, 1850.
- Richmond
- Riley
- Seneca
Pertinent Databases