Little Beard's Town, also known as Chenussio (in Seneca) and "Genesee Castle", was a powerful Seneca town in the Genesee River Valley near modern Leicester in Livingston County, New York, where Cuylerville stands today. It was named after its founder, Little Beard, a prominent Seneca sachem in the late 18th century. It had about 130 houses, fruit orchards, fields of corn and a large council building, built around a central square. The town was famous for its beautiful surroundings and the productivity of its vegetable gardens. It was located near three other Seneca towns, all of which were destroyed during the Sullivan Expedition in the American Revolutionary War.
The Seneca and three other Iroquois nations fought on the British side during the American Revolutionary War. Little Beard and his warriors participated in the Cherry Valley massacre and the Boyd and Parker ambush. In retaliation, troops of the Continental Army under Major General John Sullivan attacked Little Beard's Town and other Iroquois settlements in the Genesee and Mohawk valleys, destroying buildings and crops. The residents had to flee. Cuylerville was later built on the site by European-American settlers.
One famous resident was Mary Jemison, a Scots-Irish immigrant colonist who had been captured by the Seneca at age 15 with her family, most of whom were killed. She was adopted and married into the tribe, and lived with them all her life. She fled with the natives to more secure villages, around Niagara Falls.
More information and academic sourcing can be found at http://sullivanclinton.com