By treaty dated September 26, 1833, ending the Black Hawk War, the Chippewa, Ottawa and Potawatomi tribes ceded to the United States all lands from the west shore of Lake Michigan west to the area that the Winnebago tribe ceded in 1832, north to the area that the Menominees had previously ceded to the United States, and south to the area previously ceded by an 1829 treaty at Prairie du Chien, a total of approximately 5000000 acres .