A Church by the riverside
The first parish Church of Cardiff with its eight chapels of the Lordship of Cardiff was founded just before 1100 by Robert Fitzhamon, the first Lord of Glamorgan, on the banks of the river Taff (which gave the city its name - i.e. Caer-Dâf), and dedicated in honour of the Blessed Virgin Mary. Saint Mary Street one of the town's central thoroughfares takes its name from this ancient foundation. At this time it served a growing town along with a chapel of ease, near Cardiff Castle, dedicated to St John the Baptist, less than half a mile away at the other end of St Mary Street.
Monastic and Gloucester connections
In 1180, the parish was placed the pastoral care of the Benedictine monks of the recently founded Tewksbury Abbey in Gloucestershire's Upper Severn valley. St. Mary's was ranked as a Priory, with a small monastic community whose priest-in-charge was the Prior. From 1190 a chaplain was appointed to serve St John's as the town and its market expanded in front of the Castle. St Mary's ceased to be a priory church in 1254, when the Benedictines appointed a Vicar who was not a monk. When the monasteries were dissolved during the reformation, the right to appoint clergy to St Mary's and St John's passed to the Dean and Chapter of Gloucester Cathedral, and this remained the case until disestablishment created the Church in Wales in 1921.A section of the south choir arcade is all that remains of the original stone building of St John the Baptist. It was sacked in 1404 during the rebellion of Owain Glyndwr, then it was reconstructed in the second half of the same century creating the fine perpendicular nave and tower which are such prominent features of the city today. In the 1880's aisles were added to the north and south sides of the the nave, and in the 1960's rooms for pastoral uses were built into the south aisle giving the church its present layout.
Changing patterns of parish and city
By the time of the reformation, St John's, being much closer to the centre of commerce, had grown into a prominent church. The chapel of ease to the castle became a parish church in its own right. But, the livings of St Mary's and St John's were jointly held by the same priest. In 1607, St Mary's was seriously damaged by floods. By 1678 it was roofless and abandoned. The two parishes were merged from 1808, but when Cardiff's port began to expand as an outlet for coal exports, and the population of the area around the docks expanded the 2nd Marquis of Bute, donated a new site for a church in Bute Street, and backed the re-establishment of St Mary's as a separate Parish. This was achieved in 1846. The present St Mary's covers the redeveloped area of Cardiff Bay.
The old parish of St John the Baptist covered the entire city centre, adjacent areas of Tredegarville, Adamsdown and Cathays. By 1883 there were seven centres for Anglican worship and mission in the Parish. The first, St Andrew's started in 1879 is now home to Cardiff's Welsh speaking Anglican congregation, Eglwys Dewi Sant. St Alban's Blackweir is now home to a pentecostal congregation. The church of St James the Great was erected to serve the parochial area of Tredegarville and the Newport Road area in 1894. It was closed in 2006. The former All Saints' Adamsdown is now a warehouse. Two others remain as parish churches with St. John's. The Parish of Cathays, formed in 2007 has St Andrew and Teilo's Church built in 1901, and St Michael's, Whitchurch Road, built in 1995 to replace a Victorian tin mission church. Two of the four Parish schools built in Victorian times still flourish. St Monica's, Upper Cathays and Tredegarville Church Aided School. Both date from the late nineteenth century.