In 1822 he was appointed by President Monroe agent for Indian Affairs, to reside at St. Mary's, at the foot of Lake Superior. In the years 1825, 1826, and 1827, he attended the important convocations of the north-west tribes at Prairie du Chien, Pont du Lac, and Buttes des Morts. In 1831 he was sent on a special embassy, accompanied by troops, to conciliate the Sioux and Ojibwas, and bring the existing war between them to a close. In 1832 he proceeded in the same capacity to the tribes near the head waters of the Mississippi, and availed himself of the opportunity to trace that river, in small canoes, from the point where Pike stopped in 1807 and Cass in 1820 to its true source in Itasca Lake, upon which he entered on the thirteenth of July, the one hundred and forty-ninth anniversary of the discovery of the mouth of the river by La Salle. His account of this tour was published in New-York in 1834, under the title of An Expedition to Itasca Lake, and attracted much attention in all parts of the country.
From 1827 to 1831 Mr. Schoolcraft was a member of the legislative council of Michigan. In 1828 he organized the Michigan Historical Society, in which he was elected president, on the removal of General Cass to Washington, in 1831. In the fall of the same year he set on foot the Algic Society at Detroit, before which he delivered a course of lectures on the grammatical construction of the Indian languages,[1] and at its first anniversary a poem on The Indian Character. Guided by patriotism and good taste, he took a successful stand in the west against the absurd nomenclature which has elsewhere made such confusion in geography by repeating over and over the names of European places and characters, giving us Romes, Berlins, and Londons in the wilderness, and Hannibals, Scipios, Homers, and Hectors, wherever there was sufficient learning to make its possessors ridiculous. He submitted to the legislature of the territory a system of county and township names based upon the Indian vocabularies with which he was familiar, and happily secured its general adoption.
At Sault Ste. Marie Mr. Schoolcraft became acquainted with Mr. John Johnston, a gentleman from the north of Ireland, who had long resided there, and in the person of his eldest daughter married a descendant of the hereditary chief of Lake Superior, or Lake Algoma, as it is known to the Indians. She had been educated in Europe, and was an accomplished and highly interesting woman. After a residence there of eleven years he removed to Michilimackinac, and assumed the joint agency of the two districts. In 1836 he was appointed by President Jackson a commissioner to treat with the north-west tribes for their lands in the region of the upper lakes, and succeeded in effecting a cession to the United States of some sixteen millions of acres. In the same year he was appointed acting Superintendent of Indian Affairs for the Northern Department, and in 1839 principal disbursing agent for the same district.