Protestant Exiles from Madeira in Illinois
- A group of religious exiles from Madeira (Portuguese islands off the coast of Morocco) settled in Illinois in the 1850s. This website chronicles this episode and identifies some place names of probable Portuguese origin.
- http://lcweb.loc.gov/rr/hispanic/portam/exiles.html

Lewis and Clark Illinois
- Celebrates the bicentennial of the Lewis and Clark Expedition and the role the state played. Features a newsletter, historic sites to visit, and a calendar of events.
- http://www.lewisandclarkillinois.org/

Chronology of Illinois History
- Details in table form major dates in Illinois history from 10,0000 BC to 1999.
- http://www.state.il.us/hpa/lib/ILChronology.htm

The Underground Railroad in Illinois
- Order form, chapter overviews, and author information for this book with photographs, drawings, maps, biographical sketches, and educational activities.
- http://www.ugrr-illinois.com/

Illinois Maps
- The Perry-Castañeda Library Map Collection.
- http://www.lib.utexas.edu/maps/illinois.html

Illinois Historic Preservation Agency
- collecting, preserving, and interpreting the historical heritage and culture of the state of Illinois
- http://www.state.il.us/hpa/

Illinois Labor History Society
- Promotes the study and appreciation of the contribution made by the working people of Illinois to the betterment of life and liberty in a democratic society.
- http://www.kentlaw.edu/ilhs/

Illinois State Museum
- Fine art, anthropology, and natural history come together.
- http://www.museum.state.il.us/

Illinois History Pages
- Courtesy of Infobahn Outfitters.
- http://www.outfitters.com/illinois/history/