A treaty was made at Prairie du Chien with the Chippewas, Ottawas and Pottawattamies. Three passages date it July 29 ; P6 instead dates the Prairie du Chien treaty at which the country to the south was ceded as July 19, 1829. The cession is described two ways: P5 says these nations ceded all lands they claimed in the northwestern part of Illinois; P53 says they ceded to the United States all their land south of the Wisconsin river and covered by the Sac and Fox cession of 1804, including the lead regions and the whole of the present county.

The evidence

• “11. Two treaties were made at Prairie du Chien, on the 29th of July, 1829, and August i, 1829 : at the first date, with the Chippewas, Ottawas and Pottawattamies, by which these nations ceded all their lands which they claimed in the northwestern part of Illinois ; and at the latter date with the Winnebagoes, by which that nation ceded and relinquished all their right, title and claim to all their lands south of the Wisconsin river, thus confirming the purchase of the leadmine region. Certain grants were made to individuals, which grants were not to be leased or sold by the grantees.”

  1879-history-of-rock-county/04-wisconsin-railroads-commerce-health-statistics.md, PDF p. 212 / book p. 216

  Butterfield, C. W., et al. The History of Rock County, Wisconsin: its early settlement, growth, development, resources, etc. Chicago: Western Historical Company, 1879. Cornell University Library via the Internet Archive, archive.org/details/cu31924028871585.

  Grade A: Found on a page of one of our sources

• “August 25, 1828, the United States, by Lewis Cass and Pierre Minard, at Green bay, made a provisional treat}' with the Winnebago, Chippewa, Ottawa and Pottawattomie Indians, the latter having only "squatter's rights," for lands which were permanently ceded later. Then, by our eighth treaty, made at Prairie du Chien, July 29, 1829, the Chippewas, Ottawas and Pottawattomics ceded to the United States all their land south of the Wisconsin river and covered by the Sac and Fox cession of 1804, including therefore the lead regions and also the whole of this county. By the treaty of August 1, 1829, Winnebagoes ceded the lead regions. It is said that the lead fever of 1828 was like the gold fever of 1849 and 1850 for intensity, and caused a permanent settlement of southwestern Wisconsin several years before the eastern counties were occupied.”

  1908-brown-rock-county/02-ancient-occupants.md, Vol. 1, PDF p. 39 / book p. 31

  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