Fredonia is a borough in central Mercer County, Pennsylvania, United States. The population was 435 at the 2020 census. It is part of the Hermitage micropolitan area. The first resident of the area that became Fredonia was Levi Arnold. Arnold build a grist mill there between 1837 and 1838 and was, over time, joined by several other businesses and resi…Fredonia is a borough in central Mercer County, Pennsylvania, United States. The population was 435 at the 2020 census. It is part of the Hermitage micropolitan area. The first resident of the area that became Fredonia was Levi Arnold. Arnold build a grist mill there between 1837 and 1838 and was, over time, joined by several other businesses and residences. William Simmons built the first store in the small village. Based upon the success of his business and the further gains that could be made after the construction of a proposed railroad, Simmons purchased the land that became the borough of Fredonia and had it surveyed and divided into lots. The land came was purchased from two “Donation tracts,” which were tracts of land given to Revolutionary War soldiers in an attempt to encourage them to continue to serve. The name “Fredonia” came from Simmon’s “free” donation of the land for the town square and as a nod to the “Donation” tracts from which the land was purchased. The first post office was established in 1870 and Fredonia was officially incorporated in August 1876. Fredonia was serviced by Bessemer and Lake Erie Railroad passenger trains between 1869 and 1955. The Fredonia Volunteer Fire Department was established in 1934 and has continued to host their “Old Home Week” festival each summer since 1935.