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Cumberland County, New York was a former county of New York Province that was created in 1766 from part of Albany County on land that eventually became parts of the states of Vermont and New Hampshire. In 1772 Cumberland gave up part of her land to Gloucester County.
On 15 Janurary 1777 Cumberland County and Gloucester 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. Bennington was the other county on Vermont's west side.
- See also Cumberland County, Vermont.
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.
For records of Cumberland County, Vermont, see Orange County, Windham County, and Windsor County in Vermont, and New Hampshire. Some records created prior to 1777 may also be found at the New York State Archives in Albany, New York.