History

Pre-Columbian era

Ancient history of man goes back to the Ice Age 10,000 to 12,000 years ago at the Hiscock Site, in Byron, New York. Together with a mastodon jaw, tusks, and teeth, and assorted animal bones, researchers have found a variety of manmade tools, ceramics, metal, and leather, indicating long occupation of the site. This site is among North America’s most important for archaeological artifacts from the Ice Age.^[5][6]
Varying cultures of indigenous peoples lived in the area for thousands of years. Hundreds of years before European exploration, the Iroquoian-speaking Seneca Nation developed in the central part of present-day New York; it became one of the first Five Nations of the Haudenosaunee (Iroquois Confederacy). Beginning in 1639 and lasting for the rest of the century, the Seneca led an invasion of Western New York, driving out the existing tribes of Wenro, Erie and Neutrals.

Colonial and revolutionary era

When counties were established in New York State in 1683, the present Genesee 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. 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). In 1784 Tryon County was renamed as Montgomery County. Around this time, the Pennsylvania Colony and the Massachusetts Bay Colony also claimed the territory as their own, but New York did not enforce its territorial claim. In 1789 Ontario County was split off from Montgomery as a result of the Phelps and Gorham Purchase. Again, the county theoretically extended west to the Pacific Ocean.