by the voters in Maine on July 19, 1819, by 17,001 to 7,132). Then, on February 25, 1820, the court passed a follow-up measure officially accepting the fact of Maine's imminent statehood. Maine became the 23rd state on March 15, 1820, as part of the Missouri Compromise, which also geographically limited the spread of slavery and enabled the admission to statehood of Missouri the following year. During the abolitionist era some supporters of William Lloyd Garrison sought the secession of Essex County from the state. Boston Corner, in the southwestern corner of the state, was ceded to the state of New York in 1857, due to Massachusetts being unable to administer the hamlet. A 1919 tax-protest proposal filed in the state legislature would have created an independent State of Boston. In 1977, the islands of Martha's Vineyard, Nantucket, and the Elizabeth Islands proposed to separate from Massachusetts because of a redistricting bill that would have deprived Dukes County, consisting of Martha's Vineyard and the Elizabeth Islands, and Nantucket County of separate representation in the General Court. At local town meetings, culminating in the All-Island Selectmen's Association Conference, residents and community leaders voted in favor of secession with an "overwhelming majority". When the Nantucket state representative filed a bill with the Massachusetts Legislature, Connecticut governor Ella T. Grasso suggested that the islands join her state. Additionally, the legislatures of New Hampshire, Rhode Island and Vermont each supported the islands' annexation to their state. Although the redistricting bill passed, the state representatives pledged to assign aides for the two counties that would report to their state representative, and the area received much positive publicity. Michigan Michigan's Upper Peninsula has been the subject of proposals to create a separate state, "Superior", which would include some counties of Wisconsin, and in some proposals, parts of the Lower Peninsula. In 1979 a group called Citizens for Secession attempted to prompt leaders to move Cass County to Indiana and change the name to "Michiana County". Minnesota In the mid 19th century there had been intermittent advocacy for the Arrowhead of Minnesota, the four northeast counties of the state adjacent to Lake Superior, to join with northwestern Wisconsin and the Upper Peninsula of Michigan to form a new state to be named "North Country" or Superior, with Duluth as its capital. In March 2021, HF 2423 was introduced to the state legislature with the goal of establishing