Oneida County is a county located in the U.S. state of New York. As of the 2010 census, the population was 234,878. The county seat is Utica. The name is in honor of the Oneida, an Iroquoian tribe that lives in the region.
Oneida County is part of the Utica-Rome, NY Metropolitan Statistical Area.
When counties were established in New York State in 1683, the present Oneida County was part of Albany County. This was an enormous county, including the northern part of New York State as well as all of the present state of Vermont and, in theory, extending westward to the Pacific Ocean. This county was reduced in size on July 3, 1766 by the creation of Cumberland County, and further on March 16, 1770 by the creation of Gloucester County, both containing territory now in Vermont.
On March 12, 1772, what was left of Albany County was split into three parts, one remaining under the name Albany County. One of the other pieces, Tryon County, contained the western portion (and thus, since no western boundary was specified, theoretically still extended west to the Pacific). The eastern boundary of Tryon County was approximately five miles west of the present city of Schenectady, and the county included the western part of the Adirondack Mountains and the area west of the West Branch of the Delaware River. The area then designated as Tryon County now includes 37 counties of New York State. The county was named for William Tryon, colonial governor of New York.
During and after the Revolution, most of the Loyalists in Tryon County fled to Canada. In 1784, following the peace treaty that ended the American Revolutionary War, the name of Tryon County was changed to Montgomery County to honor the general, Richard Montgomery, who had captured several places in Canada and died attempting to capture the city of Quebec, replacing the name of the hated British governor.
In 1789, the size of Montgomery County was reduced by the splitting off of Ontario County from Montgomery. The actual area split off from Montgomery County was much larger than the present county, also including the present Allegany, Cattaraugus, Chautauqua, Erie, Genesee, Livingston, Monroe, Niagara, Orleans, Steuben, Wyoming, Yates, and part of Schuyler and Wayne Counties.
In 1791, Herkimer County was one of three counties split off from Montgomery (the other two being Otsego, and Tioga County). This was much larger than the present county, however, and was reduced by a number of subsequent splits.
In 1794, Herkimer County was reduced in size by the splitting off of Onondaga County. This county was larger than the current Onondaga County, including the present Cayuga, Cortland, and part of Oswego Counties.
In 1816, parts of Oneida and Onondaga Counties were taken to form the new Oswego County.
In 1848, John Humphrey Noyes founded a religious and Utopian community, the Oneida Community, near Oneida. Its unconventional views on religion and relations between the sexes led to much controversy. The community lasted until 1881.