At Grand Portage, where La Vérendrye’s route to the West left Lake Superior, a great fur trade depot developed in the French period and continued to prosper after the arrival of the British in 1763. The British were forced to abandon Grand Portage after 1816, but the white occupation of the site has continued to the present. Among exploring traders who entered the Minnesota country during the British period were Jonathan Carver, Peter Pond, and David Thompson.
In southern Minnesota the earliest permanent white settlement grew up in the American period near the mouth of the Minnesota River on a tract that was acquired from the Indians by Lieutenant Pike in 1805. There in 1819 Fort St. Anthony, later called Fort Snelling, was established. To manufacture lumber for the fort, a government sawmill was built at the Falls of St. Anthony in 1821-22. The first steamboat pushed up the Mississippi to the Minnesota fort in 1823. Other white settlements developed in the vicinity—Mendota across the Minnesota River from the fort, St. Paul some miles down the Mississippi, and St. Anthony and Minneapolis on the same stream above the fort at the Falls of St. Anthony. Exploration continued in the American period. After Schoolcraft discovered Lake Itasca, the source of the Mississippi, in 1832, it became possible to determine definitely the northwestern boundary of what had been the Northwest Territory. The upper valley of the Father of Waters was explored also by Pike, Cass, Beltrami, and Nicollet.
In 1805 the United States acquired from the Indians tracts of land at the mouths of the Mississippi and St. Croix rivers, and in 1837, the area between the lower St. Croix and the Mississippi. Settlements began soon afterward at Dakota (Stillwater), Marine, and St. Croix Falls, and it was due in large part to the efforts of these settlements that what is now eastern Minnesota was not included in Wisconsin. In 1848 a land boom started at St. Paul and immigration to the region increased materially. In 1849 the area of eastern Minnesota, which had been successively a portion of the Northwest, Indiana, Illinois, Michigan, and Wisconsin territories, became a part of the new Minnesota Territory, which was admitted to the Union as a state in 1858. Indian title to lands in the region was extinguished by treaties in 1854 and 1866.