1831
Lewis Cass was appointed secretary of war by President Jackson, ending his tenure as governor of Michigan Territory.
Nation and worldGrade A · 1 independent source
The evidence
“At the time that the territory, now the state of Wisconsin, became a portion of the Territory of Michigan, Lewis Cass was governor of that territory, having been appointed to that office by President Madison, October 29, 1813. He continued to hold the office of governor until 1831, when he was appointed secretary of war by President Jackson. He was the son of Jonathan and Mary Gilman Cass and the grandson of Joseph Cass, of Exeter, N.”
1908-brown-rock-county/05-historic-evolution.md, Vol. 1, PDF p. 130 / book p. 116
Brown, William Fiske, editor. Rock County, Wisconsin: A New History of Its Cities, Villages, Towns, Citizens and Varied Interests, from the Earliest Times, Up to Date. Chicago: C. F. Cooper & Co., 1908. 2 vols. archive.org/details/rockcountywiscon01brow, archive.org/details/rockcountywiscon02brow.
Grade A: Found on a page of one of our sources