Found  /  Discovery

Defining the Northwestern Limits of the New Republic

John Mitchell's renowned 1755 map was a part of King George III's extensive collection of topographical charts that helped shape American designs on Canada.

Finally on November 30, 1782, the expanded joint commission reached a conclusive peace agreement. Richard Oswald, John Adams, John Jay, Henry Laurens, and with Benjamin Franklin’s reserved approval, jointly signed the Preliminary Articles of Peace. The Americans had only partially incorporated their Second Continental Congress’s 1779 wishes for the northwestern boundary. Congress had specified the line should start, in part from the intersection of the 45th N parallel and the St. Lawrence River and proceed directly to the southern end of Lake Nipissing and further to the source of the River Mississippi. Instead, the finalized northwest line, after reaching the St. Lawrence, continued westward through the center of the Great Lakes (excluding Michigan) and from the northwest shore of Lake Superior headed inland along a water and land trade route to the most northwestern part of Lake of the Woods. It was then to proceed due west until it intersected the conjectured Mississippi at a likely point south of 50° N. The start of the due west line is shown on Oswald’s map (see MS – 9).

Reaching a consensus on the extreme northwest corner of the boundary posed difficulties for Franklin, since he had earlier maintained the river’s source was located south of Lake of the Woods. However, to conclude the signing of the Preliminary Articles of Peace, Oswald and Franklin must have remained mute about Carver’s source of the Mississippi and acquiesced to the stance of their fellow commissioners and others who wished not to deviate from Mitchell’s authoritative, yet outdated and inaccurate river details. Ten months later the boundary as delineated in the Preliminary Articles of Peace was, word for word, ratified in the 1783 Definitive Treaty of Paris, Article Two.