Campbell was first settled around 1801. The town was formed in 1831 from the Town of Hornby. It is located on the west side of Interstate 86 by the Cohocton River. County Road 125 is Main Street.
Source: Campbell, NY on en.wikipedia.org

On April 15, 1831, it was named in honor of Rev. Robert Campbell, an early proprietor. It is an interior town, lying southwest of the centre of the county, bounded north by a portion of Bath and the town of Bradford, east by Hornby, south by Erwin and a part of Addison, and west by Thurston.
Source: rootsweb.ancestry.com

The district was called township 3, range 2, Phelps and Gorham purchase. The proprietary just mentioned sold this township to Prince Bryant, a Pennsylvanian, and conveyed it by deed dated September 3, 1789. It changed hands many times in parcels. Rev. Robert Campbell was the leader but the town was named after the family in general. In local history in the county, Campbell has always been regarded as one of the rough, mountainous towns. In 1852 the Buffalo, Corning and New York Railroad was built through the Conhocton valley.
Source above 2 paragraphs: history.rays-place.com