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Winnebago County

County Clerk or Recorder
Winnebago County Administration Building
404 Elm St.
Rockford, IL 61101
815-319-4250 – County Clerk
815-319-4325 – Recorder
Circuit Clerk
Winnebago County Courthouse
400 W. State St., Rm. 101
Rockford, IL 61101
815-319-4500
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 the Winnebago Indian tribe who once occupied that part of northern Illinois. The Indian word Winnebago translates to "fish eater."

Present area, or parts of it, formerly included in
- Eastern Part
- 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
- Western Part
- 1827–1836 – JoDaviess
- 1825–1827 – Putnam
- 1823–1825 – Fulton
- 1821–1823 – Pike
- 1817–1821 – Bond
- 1812–1817 – Madison
- 1801–1812 – St. Clair
County Seats
- 1836–1839 – Winnebago—Temporary designation.
- 1839–present – Rockford
History of county governing board
- 1836–1850 – County Commissioners’ Court
- 1850–present – County Board of Supervisors
Township Government
- Adopted – November 6, 1849
Township Names
- Burritt
- Cherry Valley – Name changed from New Milford circa 1869.
- Durand – Name changed from Howard circa 1869.
- Harlem
- Harrison
- Laona
- Owen
- Pecatonica – Name changed from Lysander (date unknown).
- Rockford
- Rockton
- Roscoe
- Seward
- Shirland
- Winnebago – Name changed from Elida circa 1869.
Township Map
Pertinent Databases