This history of St. Cuthbert's Parish in St. Theresa's, Prince Edward Island traces the development of the parish from a mission church to 1970. The history includes a list of resident priests, a list of priests and sisters from St. Cuthbert's Parish and a list of the first Catholic settlers if the Mission of St. Cuthbert.

In the 1840s, following an influx of Irish Catholic immigrants to the Fort Augustus, Prince Edward Island, area, a mission church was established on the Baldwin's Road. This church, which had been dedicated to St. Cuthbert, served the mission for nearly thirty years when it was decided that a larger church was required. This second church stood from 1875 until 1879 when it was destroyed by a windstorm. Construction immediately started on a new church which was completed and dedicated to St. Theresa in 1886. In 1912 the parish hired architect James Harris to design a a larger church. Upon its completion in 1919 the new church was returned to the patronage of St. Cuthbert.