According to tradition, the ecclesial presence at Kilfenora began with
Saint Fachanan, who founded a church here in the 6th century. The first building was probably made of wood and followed by a stone construction. That church was burned down in 1055 by Murchad O'Brien. The diocese corresponded with the
ancient territory of Corcomroe. Kilfenora Cathedral is dedicated to St. Fachtna (also known as St. Fachanan or St. Fachtnan). The present structure dates to between 1189 and 1200. It was built in the so-called transitional style with a
nave and a
chancel. These were later separated and by 1839, "thirty-six feet of the east end" were roofless. Part of the
ecclesiastical province of Cashel, the diocese only extended over 200 square miles of very thinly populated land. It was reckoned the poorest diocese, with only 13 parishes. Demand for the position of bishop thus was not great, but for 1189 a bishop is recorded. Following the
Reformation in Ireland, the Catholic Church continued to appoint diocesan bishops in parallel with those of the established church. This practice ceased with the succession of James Augustine O'Daly (d. 1749). In 1750, the diocese was united with
Kilmacduagh. In 1883 "Kilfenora and Kilmacduagh" was again merged with the diocese of
Galway. Today, the bishops of Galway and Kilmacduagh are styled "Bishop of Galway and Kilmacduagh and Apostolic Administrator of Kilfenora"; while the bishop administers the diocese, in
Canon Law, he does so as representative of the
Pope. In the Church of Ireland, Kilfenora was merged in turn with the dioceses of Limerick (1606–07), Tuam (1617-1742), Clonfert (1742-1752), Killaloe (1752-1976) and again Limerick (since 1976). In 1661
Samuel Pullen was made
Archbishop of Tuam and Kilfenora became part of his province. ==Description==