The first known exploration was conducted by Sieur des Groseilliers and Pierre Radisson, fur traders who came by way of Lake Superior in 1659–60. In the northern area they found Chippewa Indians; in the south, Sioux (Dakotas). In 1679 Sieur Duluth traveled with the Sioux to Mille Lacs Lake and claimed the upper Mississippi valley for France. The next summer Father Louis Hennepin journeyed from the mouth of the Illinois River up the Mississippi to the Falls of St. Anthony at the future site of Minneapolis.

The French continued their explorations of the region, and in 1732 the La Vérendryes established a trading post at Lake of the Woods. Grand Portage, at the mouth of the Pigeon River, was the area's main post in the early fur trade. In 1763 eastern Minnesota, with the rest of New France, passed to Great Britain. The area west of the Mississippi had, as part of Louisiana, been ceded to Spain in 1762.