1853
The removal of the Winnebagoes was continued up to 1853, when from 700 to 900 still remained.
The regionGrade A · 1 independent source
The evidence
“In 1846 some 1,250 Winnebagoes came back from Iowa and settled along the Fox and Wisconsin and the Kickapoo and Lemonweir valleys. The process of removal was continued up to 1853, when from 700 to 900 still remained. In my early boyhood of those years, in Beloit, I remember seeing often little bands of those Indians in our streets.”
1908-brown-rock-county/02-ancient-occupants.md, Vol. 1, PDF p. 42 / book p. 33
Brown, William Fiske, editor. Rock County, Wisconsin: A New History of Its Cities, Villages, Towns, Citizens and Varied Interests, from the Earliest Times, Up to Date. Chicago: C. F. Cooper & Co., 1908. 2 vols. archive.org/details/rockcountywiscon01brow, archive.org/details/rockcountywiscon02brow.
Grade A: Found on a page of one of our sources