On the Eve of the Reformation, there is a picture of a thriving religious life with vicars, chaplains, chantry priests, two altars dedicated to Our Lady (the high altar and nave altar) and one in honour of St Nicholas
Mass was offered twice daily (the Mass of the Day and of Our Lady) and Sundays and holy days were celebrated with great solemnity. St Mary’s had gained many properties and gardens leased out for the growing of flax, and they received a substantial amount of income from tithes. However, things were beginning to change
The Benedictines appear to have built the chapel of St John’s soon after the building of the priory. The first recorded reference to it is 1180, built to cater for the spiritual needs of parishioners of St Mary’s who lived in that area which now had the highest density of population, immediately south of the castle walls. By 1190 it had its own chaplain – Augustine – and it became quickly popular with the townspeople
By 1242 St John’s standing was such that the Archdeacon of Llandaff attempted to separate it from St Mary’s and create a new parish. This was strongly and successfully resisted by the Prior of St Mary’s, Richard de Derby, who appealed the following year to the newly elected Pope Innocent IV against this invasion of rights.
St John’s remained as a dependant chapel of St Mary’s right through to the Reformation, and it wasn’t until 1535 that St John’s had become a separate benefice, although they shared a single vicar, a situation which continued until 1843
By the sixteenth century, because of its situation, and the patronage of the Lords of Cardiff, St John’s had become the wealthier and more popular church. During the twenty years from 1453, the church was entirely rebuilt, and the West Tower which still stands today began to emerge. By the end of that century, St John’s was allowed to conduct baptism, marriages and burials church, rather than at St Mary’s.
There may be trouble ahead...!
Meanwhile, the doom of St Mary’s Priory church was looming. The flood of 1607 would weaken its foundations, and the battles of the Civil War of the 1640s would damage it further still, until in 1678 it became just a roofless shell. However, the influence of St Mary’s was tenacious. Up until the 1730s, the ruins still provided a place for baptisms, although the last recorded burial was 23 years earlier when John Bawdrip was laid to rest.
John Speed's 17th century map of Cardiff
St John's Church, Cardiff showing the Medieval West Tower