Guilford is a town in Chenango County, New York, United States. The town is on the eastern border of the county. The population was 2,922 at the 2010 census. The land was purchased from the Oneida people in 1785. The town was first settled circa 1787. One of the first settlements was in what is now known as East Guilford, by the Mercereau brother…Guilford is a town in Chenango County, New York, United States. The town is on the eastern border of the county. The population was 2,922 at the 2010 census. The land was purchased from the Oneida people in 1785. The town was first settled circa 1787. One of the first settlements was in what is now known as East Guilford, by the Mercereau brothers. They built a mill on Guilford Creek at Indian Orchard Falls, along the Catskill Turnpike.