<P> Although the Upper Peninsula nominally became United States territory with the 1783 Treaty of Paris, the British did not give up control until 1797 under terms of the Jay Treaty . As an American territory, the Upper Peninsula was still dominated by the fur trade . John Jacob Astor founded the American Fur Company on Mackinac Island in 1808; however, the industry began to decline in the 1830s as beaver and other game were overhunted . </P> <P> When the Michigan Territory was first established in 1805, it included only the Lower Peninsula and the eastern portion of the Upper Peninsula . In 1819, the territory was expanded to include the remainder of the Upper Peninsula, all of Wisconsin, and part of Minnesota (previously included in the Indiana and Illinois Territories). When Michigan was preparing for statehood in the 1830s, the boundaries proposed corresponded to the original territorial boundaries, with some proposals even leaving the Upper Peninsula out entirely . Meanwhile, the territory was involved in a border dispute with the state of Ohio in a conflict known as the Toledo War . </P> <P> The people of Michigan approved a constitution in May 1835 and elected state officials in late autumn 1835 . Although the state government was not yet recognized by the United States Congress, the territorial government effectively ceased to exist . A constitutional convention of the state legislature refused a compromise to accept the full Upper Peninsula in exchange for ceding the Toledo Strip to Ohio . A second convention, hastily convened by Governor Stevens Thomson Mason, consisting primarily of Mason supporters, agreed in December 1836 to accept the U.P. in exchange for the Toledo Strip . </P> <P> In January 1837, the U.S. Congress admitted Michigan as a state of the Union . At the time, Michigan was considered the losing party in the compromise . The land in the Upper Peninsula was described in a federal report as a "sterile region on the shores of Lake Superior destined by soil and climate to remain forever a wilderness ." </P>

When did the up become part of michigan