History

Whiteside County was organized by European Americans in 1836 from parts of Jo Daviess and Henry counties. It was named for General Samuel Whiteside, an Illinois officer in the War of 1812 and Black Hawk War. Whiteside County's boundaries have remained unchanged since its creation in 1836. County organization was completed in 1839.

Named for Samuel Whiteside, a Colonel of the Territorial militia, Representative in the First General Assembly, and Brigadier General of the militia during the Black Hawk War.

History Books:

• Portrait and Biographical Album for Whiteside County, IL dated 1885 (free online in PDF format)


• Illinois Supreme Court Historic Preservation Commission (has nice photos)


• 1877 History of Whiteside County Illinois - includes biographical and family sketches

Present area, or parts of it, formerly included in:

• 1837–1839 – Attached to Ogle (Laws, 1836, p. 277)
• 1836–1837 – Attached to JoDaviess (Laws, 1836, p. 277)
• 1827–1836 – JoDaviess
• 1825–1836 – Henry
• 1825–1827 – Putnam
• 1823–1825 – Fulton
• 1821–1823 – Pike
• 1812–1821 – Madison
• 1795–1812 – St. Clair

County Seats:

• 1839–1841 – Lyndon
• 1841–1842 – Sterling
• 1842–1846 – Lyndon
• 1846–1847 – Circuit Court at Sterling, County Commissioners’ Court at Lyndon
• 1847–1857 – Sterling
• 1857–present – Morrison

History of county governing board

• 1839–1849 – County Commissioners’ Court
• 1849–1852 – County Court
• 1852–present – County Board of Supervisors

Township Government adopted - November 4, 1851