Once built into the north side of the churchyard wall and now given a less weathered home above the doorway into the West porch is a small stone corbel-head. It is all that remains of the ancient church of St Mary. Whilst set in stone, it's a nodding gesture to the past
John Speed's 17th century map of Cardiff
William the Conqueror
However, it was also to serve as a parish church for the community which extended beyond the immediate area, and small chapels of ease were built in the various areas – including S Margaret of Antioch at Roath, St Denys at Lizvane and Llanishen, the ancient Celtic cell of St Edeyrn was rebuilt in Llanedeyrn, and the Church at Llandough, the ancient Celtic monastery of St Gyngar was placed in the charge of St Mary’s. By 1102, St Mary’s was responsible for the spiritual life of Cardiff and at least six outlying hamlets.
Towards the end of the twelfth century the church was rebuilt at the expense of William Earl of Gloucester, Lord of Cardiff and grandson of King Henry I, perhaps to coincide with the growth in devotion to the recently martyred Thomas Becket at Canterbury, who had been canonised just two years after his death in 1170
There is no clear description of any of the two church buildings – the first illustration comes much later in the seventeenth century map of Cardiff by John Speed, who shows a typical Norman building, cruciform shaped, with a lofty square central tower.
St Mary’s history as a priory church, however, was short lived. By 1221 the monks had been withdrawn, although the prior remained as a steward of Tewkesbury’s property for another hundred years. The last known prior was Simon in 1295. By 1318, Pope John XXII had prohibited the living of single, solitary monks and so Simon, very likely, was recalled to the Mother house, leaving the church and parish to the care of a vicar, an office which dates back to 1254 and who in 1291 was in receipt of the stipend of four monks. By the end of the fourteenth century, the system of Vicar and a staff of chaplains to serve the parish was well established.
1066 is a year etched in the history of Britain, when William the Conqueror defeated Harold, the last Saxon King of England at the Battle of Hastings. However, it was not for another thirty years that William’s son of the same name advanced beyond the West of England into Wales.
Iestyn ap Gwrgan, the late native prince of Morgannwg, gave way to Robert Fitz Hamon and Fitz Hamon began to build upon the ancient foundations of the old Roman settlements. He brought with him his chaplain, also named Robert (a popular name) who became Cardiff’s first recorded prior.
By 1100 the priory had been built and granted to the abbey of Tewkesbury, and so was dependant on that abbey, which staffed it with Benedictine monks and a prior. It was built on the open land of the river to the south of the new castle.
The corbel head from the original Norman priory church