In 1860 the Bankheads, southern converts to Mormonism, brought their slaves, who remained until 1896. Wellsville was the only community in the Valley were blacks lived and worked their land.

Wellsville was surveyed in 1863 by James H. Martineau, who put into effect what was a Mormon community concept: four-square orientation with the points of the compass with the streets meeting at right angles. The land was divided into ten-acre blocks, each divided into eight lots of 1.25 acres. As bishop, William H. Maughan had de facto powers in civil affairs. As early as 1861 a justice of the peace, marshal, road supervisor, and town clerk were serving; but it was not until 19 January 1866 that Wellsville was incorporated as a city with a full slate of municipal officers with William H. Maughan as mayor.

This predominantly Mormon community built a beautiful Gothic Revival-style tabernacle between 1902 and 1908. It was built by volunteer labor with local building materials and has stood in the town square as a sentinel and been the center of activity for both church and community for almost one hundred years. There are now five LDS Wards housed in three buildings, and the Wellsville Stake was organized 17 June 1979. There has been an organized choir since early settlement, and each ward still supports a choir that provides music for meetings, special programs, and Founders' Day.