Old Map of the Great Lakes and Upper Mississippi Valley, Northern America, c1780

About this sheet

Partie Occidentale du Canada, an original copper engraved map of the Great Lakes and the upper Mississippi valley by Rigobert Bonne, from the atlas prepared for Guillaume Raynal's Histoire philosophique et politique des établissements et du commerce des Européens dans les deux Indes, c.1780. The title reads "Partie Occidentale du Canada, contenant les cinq Grands Lacs, avec les Pays circonvoisins". The sheet has a hand-colored coastline and a broad yellow border.

Lakes Superior, Michigan, Huron, Erie and Ontario are drawn in the form French mapmakers knew them, ringed with color. The map names the lands of the Sioux, the Iroquois, the Illinois, the Assiniboine and other peoples, and marks forts and routes, among them Chicagou, Detroit and Michillimackinac. Lake Superior still carries a number of islands that were later shown not to exist. Rivers run west toward the Mississippi, and the upper Mississippi is shown without a known source.

The map reflects the geography of the region as it stood before the American Revolution settled the border, and Bonne's small-scale maps were widely used as the most up to date summary of French knowledge of the interior.