It may have been the flood of 1607 and the embattled bruises of the Civil War four decades lates which sealed the fate of St Mary's Priory Church, but the root cause was politica and fiscal. The state, under Edward VI, confiscated the chantry funds from St Mary's. These funds had been used to keep the bridge, walls and quay in repair in the face of the "rage of the Taff" caused by the meeting of high tides in the Bristol Channel.
The town had had created a system of weirs, which they maintained by the chantry funds. The confiscation of these funds meant that the weirs fell into disrepair. In 1578, there was a considerable flood in the parish of St Mary's, and by the end of the century the uncontrolled river was beginning to encroach the boundary wall of the churchyard.
Then, on 20 January 1607, a severe flood felt across the south west of England and south east Wales. The flood washed away part of St Mary's churchyard and probably through the building itself.
A pamphlet published after the flood entitled "God’s warning to his people of England" states:
“The foundations of many Churches and houses, were in a manner decayed, and some caryed quite away, as in Cardiffe, in the county of Glamorgan there was a great part of the Church next the Water side eaten downe, with the Water, many houses and Gardens there, which were neere the water side, were all overflowen, and much harme done.”
However, the church wasn't quite carried away. The foundations may have been weakened but for some years after this the church was still used regularly and John Speed's seventeenth century map shows an intact building. Speed added a warning, however, by saying that the River Taff was "a foe of St Marie's Church, with undermining her foundations and threatening her fall."
Despite the injuries to the building and the warnings of Speed, both the Dean and Chapter of Gloucester Cathedral and the townspeople overlooked their responsibility to keep the church in good repair.
Contemporary depiction of the 1607 flood
(the church is thought to be
St Mary's at Nash, near Newport)
By artist unknown - Mike Kohnstamm: Great Flood of 1607, Public Domain
From 1642 until 1649, the Civil War between King Charles I and his Parliament sealed the fate of St Mary's. The seventeenth century historian Edward Lhuyd said the War caused the final ruin of the church.
The absentee vicar, Theodore Price, was removed by the Parliamentary commissioners and, in two conflicts within the town, when the Royalists attempted to regain control of the castle and borough, St Mary's suffered further damage. By 1678, the Church was a roofless shell, the result of the collapse of its great central tower. What remained of the church was in danger of being swept away for ever.
After the resoration of King Charles II in 1660 no services were held there but burials continued, and some baptisms too. It's days were numbered, waiting to re-emerge, in name only, two hundred years later.
William Seymour, Marquess of Hertford who crossed the channel from Minehead in 1642 to attempt to gain control of the castle and borough from the Parliamentarians. During the conflict, St Mary's Priory Church was further damaged.
Portrait attributed to Gilbert Jackson (1622 - 1640) - Sotheby's, Public Domain