The Mt. Stewart/St. Peter's Bay pastoral charge of the United Church of Canada was created in 1961 with the amalgamation of the two charges of Mt. Stewart and West St. Peters, and, St. Peters Bay, Marie & Greenwich which had existed since Church Union in 1925. The charge is composed of the congregations of Mt. Stewart, St. Peters and Morell. Churches at Marie, Donaldston and Bristol were either torn down or sold as Marie joined with Morell to build the Peter Gordon Memorial Church in Morell in 1962, and Donaldston joined with Mt. Stewart to worship in St. John's United Church, originally built in 1854. The people of St. Peters and Greenwich continued to worship in the St. Peters United Church which had been built as a Presbyterian Church in 1886.

In 1806, the communities of St. Peters Bay, Covehead and Bay Fortune formed the first Presbyterian charge in Prince Edward Island and Rev. Peter Gordon was inducted as minister of the charge. The first Presbyterian church was also built in that year at St. Peters. In 1843 the congregation was divided into two - West St. Peters and Cove Head forming one and East St. Peters and Bay Fortune the other. By 1852 the congregation had grown so much that it was deemed advisable to separate West St. Peters from Cove Head. In 1858 Bay Fortune and Souris were separated from East and West St. Peters and organized into a separate charge. The following year, West St. Peters and Mount Stewart were disjoined from East St. Peters. A new church, built by William Coffin, opened in St. Peters in 1886. Rev. J.W. MacKenzie was the first pastor of the St. Peters Bay congregation which included Marie and Greenwich. A church was also built at Marie in 1889. In 1925, without a dissenting voice, the Presbyterian congregation of St. Peters Bay joined with the Methodists to become the St. Peters Bay, Marie, Greenwich pastoral charge of the United Church.

When the Presbyterian Church was built at Mount Stewart in 1853, the congregation was part of the East and West St. Peters charge under the ministry of Rev. Henry Crawford. In 1859, Mount Stewart and West St. Peters were disjoined from East St. Peters to become a separate charge. Ministers to this congregation included Revs. Alexander Falconer, D.W. Cameron, William R. Frame and A.B. MacLeod. In 1925, the majority of the Presbyterians of Mt. Stewart joined with the Methodist congregation to become part of the Mt. Stewart/West St. Peters charge of the United Church of Canada worshipping at St. John's United Church. A small number of dissenters took ownership of the former Methodist Church and formed St. David's Presbyterian Church, part of the Mt. Stewart, Marshfield, Harrington, Highfield charge.

Although Thomas Dawson Methodist missionary preached in Prince edward Island as early as 1801, it wasn't until 1859 that Mt. Stewart was included in the Methodist circuit to be visited from Charlottetown. By 1862 this had changd to the Souris Mt. Stewart circuit with Rev. W.C. Brown as pastor. In 1871, the original church built at Cranberry Point was moved into the town and in 1876 Mt. Stewart became the centre of a permanent Methodist circuit made up of Marie, Mt. Stewart and Black River which also included the communities of Dunstaffnage, Fanning Brook, and Church Road. As early as 1920 Presbyterians and Methodists were alternating services paving the way for Church Union in 1925 when they became one congregation, the Mt. Stewart and West St. Peters pastoral charge of the United Church.