This is an account by Henry Rowe Schoolcraft (1793-1864) of his discovery of the Mississippi River's source, Lake Itasca, in 1832. Schoolcraft was an Indian agent for the region, and he assembled an expeditionary party of thirty, including Ozawindib (an Ojibway guide and interpreter), an army officer, a surgeon, a geologist, and interpreter, and a missionary. They set out with instructions from Secretary of War Lewis Cass to effect a permanent peace among the region's Native Americans, persuade them to be vaccinated against smallpox, acquire demographic and scientific information, and establish definitively the origin of the Mississippi. Expedition Through the Upper Mississippi contains anecdotes and observations about the beliefs, customs, and history of the Chippewa [Ojibway] as well as the Sioux [Dakota], the Fox [Mesquakie], the Sauk, the Menominee, the Mandans, and various other Native American groups. The narrative proceeds chronologically along the route the expedition followed, with detailed descriptions of geographical features. This volume also includes a short account of a trip along the St. Croix and Burntwood (Brule) River, and has an appendix containing statistical and linguistic data, a list of shells collected by Schoolcraft in the West and Northwestern territories, official reports, a speech by six Chippewa chiefs about the war delivered at Michilimackinac in July 1833, and a discussion of the Upper Mississippi's lead-mining country.