The county seat is Schoharie, a name that comes from a Mohawk language meaning "floating driftwood." The Mohawk, one of the original Five Tribes of the Iroquois League, were historically based in central New York west of the Hudson River.
The large territory of the county (much of upstate and western New York) was long occupied by the Mohawk Indians and, to the west, other four tribes of the Iroquois League (increased to six with the migration of the Tuscarora from the South to New York in 1722). After European colonization of the Northeast started, the Mohawk had a lucrative fur trade with the French coming down from Canada, as well as the early Dutch colonists, and later British and German colonists.
Some Palatine Germans, who worked in camps on the Hudson to pay off their passage in 1710, later settled in this county in the 1720s and 30s. In addition, Scots-Irish immigrants settled in the present Schoharie County area before the Revolutionary War, especially near Cherry Creek.
After Great Britain defeated the Dutch and took over their colony, they began to establish counties in the New York territory in 1683. The present Schoharie County was first 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. In theory, it extended westward to the Pacific Ocean, as the colonists wanted to keep their options open. 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 part of Vermont.
On March 12, 1772, what was left of Albany County was split into three parts, one remaining under the name Albany County. Tryon County was formed from the western portion of the territory (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 was eventually organized into what are now 37 counties of New York State. The county was named for William Tryon, colonial governor of New York.
In the years prior to 1776, as social and political tensions rose in the colony, most of the Loyalists in Tryon County, then on the frontier, fled to Canada. In 1784, following the peace treaty that ended the American Revolutionary War and establishment of states, the new government changed the name of Tryon County. They renamed it as Montgomery County to honor General Richard Montgomery, who had captured several places in Canada and died trying to capture the city of Quebec.
The state continued to organize new counties. In 1789, Montgomery County was reduced in size by the splitting off of Ontario County. It was originally much larger than the present county, including present-day Allegany, Cattaraugus, Chautauqua, Erie, Genesee, Livingston, Monroe, Niagara, Orleans, Steuben, Wyoming, Yates, and part of Schuyler and Wayne counties.
In 1795, Schoharie County was created by joining portions of Otsego and Albany counties.
This was an area of fighting during the American Revolutionary War. On the frontier, colonists were subject to raids by British and their Iroquois allies. Four of the six tribes allied with the British, hoping to repel the colonists from their territory.