Please choose a county in Illinois:

After separating the census records into groups by state, the federal government subdivided these records into county groups. Searching for an ancestor on the county level provides a smaller region for research if you remain uncertain about the specific township where your ancestor resided. Researchers should also be aware of boundary line or jurisdictional changes through time. These changes may affect where an ancestor was enumerated on the census, so it remains important to search the counties surrounding the area where your ancestor lived.