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Residence place: Winnebago il 1840 [813 people; Ancestry shows 795]
I would imagine the majority of people who resided here 1839 would be here 1840.
There isn't a twp breakdown on the census.
Doesn't have a date, but maybe your families are still there. Enlarge Rockford, the names are very clear.https://www.loc.gov/resource/g4103w.la002129/
What names are you researching?