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Gloucester County, New York was a former county of New York Province that was created in 1770 from part of Albany County on land that eventually became parts of the states of Vermont and New Hampshire. In 1772 Cumberland County (to the south) gave up part of her land to increase the size of Gloucester County (to the north) which had given part of her land to Charlotte County (to the west). Gloucester County was roughly equivalent to modern Orange, Caledonia, and Essex counties in Vermont and the eastern parts of Washington, Lamoille, and Orleans counties. For a map see the bottom of this page.
On 15 Janurary 1777 Gloucester County and Cumberland County were ceded from New York to Vermont. The two counties were combined into a single short-lived county called Cumberland on the east side of Vermont. See also Cumberland County, Vermont. At the same time the east of Lake Champlain part of Charlotte County was also ceded from New York to Vermont. This Charlotte County land became the other Vermont County, Bennington, on Vermont's west side.
In 1781 Vermont extinguished Cumberland County and split her into four pieces: Orange County, Windham County, Windsor County, and Washington (old) County. The next year Washington (old) County became part of the State of New Hampshire.
In 1784 the remaining fragment of Charlotte County on the western side of Lake Champlain was renamed to Washington County, New York.
For records of old Gloucester County, after it became part of Vermont, see Orange County, Vermont, part of Cumberland County, Vermont 1777 to 1781. Some Gloucester County records created prior to 1777 may also be found at the New York State Archives in Albany, New York.