# Treaty of Prairie du Chien *1830 treaty ceding territory to the United States and creating the Lake Pepin "half-breed" tract, the basis of a pending federal claim* Treaty of Prairie du Chien is a name shared by four treaties that the United States concluded with Native American nations of the Upper Midwest at Prairie du Chien, Wisconsin: one in 1825, two in 1829 and one in 1830.[^1] Under the last of these, the Sac and Fox, Sioux, Omaha, Iowa, Otoe and Missouria gave up land to the United States.[^1] In the [[Minnesota]] record, the 1830 instrument is the origin of the Lake Pepin "half-breed" tract.[^2][^3] The [[Minnesota Historical Society]]'s MNopedia entry places the tract west of [[Lake Pepin]]. It gives the tract's size as 320,000 acres, an area of roughly twenty-five by thirty-two miles.[^3] On October 13, 2025, [[Mdewakanton]] / "half-breed" descendants of the Lake Pepin reservation sued the United States in the U.S. Court of Federal Claims. They seek federal recognition and approximately $5 billion.[^4][^5] The suit is grounded in the 1830 treaty and in the 1851 Treaties of Traverse des Sioux and [[Mendota]]. The record describes those 1851 treaties as having removed the tract's protections.[^4] The record lists the matter as pending.[^4] ## Background The four instruments that share the name were each signed at Prairie du Chien, Wisconsin. The 1830 treaty is the fourth.[^1] The first is the Treaty with the Sioux, etc., dated August 19, 1825.[^6] Its Article 5 sets a boundary between the Sioux and the Chippewa. That boundary runs to the Rum River and on to a point of woods "half a day's march from the Mississippi."[^6] ## Lake Pepin tract The Lake Pepin tract was established by the 1830 Treaty of Prairie du Chien.[^2][^3] MNopedia gives its extent as 320,000 acres west of Lake Pepin.[^3] The claimants' suit also describes the tract as about 320,000 acres. The suit treats the 1830 treaty as the instrument that set the tract aside, and the 1851 Traverse des Sioux and Mendota treaties as the instruments that removed its protections.[^4] The record does not carry the text of the 1830 treaty's tract clause or of the 1851 provisions. ## Active matters *Mdewakanton / Sioux half-breed descendants v. United States (Lake Pepin reservation; federal recognition)* was filed in the U.S. Court of Federal Claims on October 13, 2025, which was [[Indigenous Peoples' Day]].[^4] The suit names the 1830 Treaty of Prairie du Chien and the 1851 cessions as its instruments. It seeks federal recognition, land-related relief and approximately $5 billion.[^4][^5] Counsel for the plaintiffs is [[Erick Kaardal]].[^4][^5] The record lists the case as pending and does not give a docket number.[^4] ## In the Minnesota record ### Who - The 1830 treaty was concluded between the United States and the Sac and Fox, Sioux, Omaha, Iowa, Otoe and Missouria.[^1] - The plaintiffs in the pending federal claim are Mdewakanton / "half-breed" descendants of the Lake Pepin reservation, represented by Erick Kaardal.[^4][^5] ### What - The 1830 treaty recorded cessions of territory to the United States.[^1] - The 1830 treaty established the Lake Pepin "half-breed" tract.[^2][^3] - Article 5 of the 1825 treaty set the boundary between the Sioux and the Chippewa.[^6] ### When - The first Treaty of Prairie du Chien is dated August 19, 1825.[^6] - The fourth treaty was signed in 1830.[^1] - The federal complaint was filed on October 13, 2025.[^4] ### Where - All four treaties were signed at Prairie du Chien, Wisconsin.[^1] - The Lake Pepin tract lay west of Lake Pepin.[^3] - The claim is before the U.S. Court of Federal Claims.[^4] ### Why - The complaint rests on the 1830 treaty and on the 1851 Traverse des Sioux and Mendota treaties, which the record describes as having removed the tract's protections.[^4] The record does not establish why the 1851 instruments were drafted as they were. ### How much - The Lake Pepin tract measured 320,000 acres, roughly twenty-five by thirty-two miles.[^3] - The federal complaint seeks approximately $5 billion.[^4][^5] ## See also - [[Mdewakanton / Sioux half-breed descendants v. United States (Lake Pepin reservation; federal recognition)]] - [[Mdewakanton]] - [[Lake Pepin]] ## Notes [^1]: Wikipedia contributors, *Treaty of Prairie du Chien* (revision 1283667740, retrieved October 26, 2026) — identifies four treaties signed at Prairie du Chien, Wisconsin, and records that in the 1830 fourth treaty the Sac and Fox, Sioux, Omaha, Iowa, Otoe and Missouria ceded territory to the United States. https://en.wikipedia.org/wiki/Treaty_of_Prairie_du_Chien [^2]: Library of Congress, *1830 Treaty of Prairie du Chien* (catalogue claim:link row 21) — Half-Breed Tract origin in the 1830 treaty. https://www.loc.gov/ [^3]: Minnesota Historical Society, *MNopedia: Lake Pepin Tract* (n.d.) — tract established by the 1830 Treaty of Prairie du Chien; 320,000 acres west of Lake Pepin, roughly twenty-five by thirty-two miles. https://www.mnhs.org/mnopedia/search/index/place/lake-pepin-tract [^4]: U.S. Court of Federal Claims, *Mdewakanton / Sioux half-breed descendants v. United States*, complaint (filed October 13, 2025) — claim grounded in the 1830 treaty's Lake Pepin tract and in the 1851 Traverse des Sioux and Mendota treaties; seeks federal recognition and approximately $5 billion; counsel Erick Kaardal; pending as of record. https://turtletalk.blog/wp-content/uploads/2025/10/complaint.pdf [^5]: CBS Minnesota, *Sioux descendants announce lawsuit against United States over land, recognition* (October 2025) — report of the filing, relief sought and counsel. https://www.cbsnews.com/minnesota/news/sioux-descendants-announce-lawsuit-united-states-land-recognition/ [^6]: Kappler compilation, Oklahoma State University, *Treaty with the Sioux, etc., 1825* (August 19, 1825) — Article 5 boundary between the Sioux and the Chippewa, including "thence to Rum River, crossing it at the mouth of a small creek called choaking creek." https://treaties.okstate.edu/treaties/treaty-with-the-sioux-etc-1825-0250