St John's Priory;Priory of St John and St Teulyddog (Augustinian), Carmarthen
Overview
Carmarthen Priory grew from a place of worship older than the Norman conquest and became a house of Augustinian canons around 1125. It was looted during Owain Glyndŵr's rising and closed in 1537; its gate, wall fragments and uncovered foundations survive, while it is closely linked with the Black Book of Carmarthen.
Foundation and growth
The site began as the old Welsh church of Llandeulyddog, perhaps as early as the sixth century. Monks linked to Battle Abbey occupied it briefly after the Norman conquest, before Bishop Bernard of St Davids established a community of Augustinian canons around 1125.
People and events
The Black Book of Carmarthen, the earliest complete surviving book written in Welsh, was probably copied here around 1250. Owain Glyndŵr's rising brought looting in 1403. Twelve canons remained near the end, with many more people working in and around the priory each day.
Damage, loss and survival
The priory closed in February 1537 and part became a mansion. Most living ranges were cleared for a lead works around 1781, and railway building removed more in the 1850s. The gatehouse, now four homes, wall pieces and foundations found in 1979 remain.
Why it mattered
This was a religious centre across the change from native Welsh worship to Norman rule and later church reform. Its strongest wider legacy is the Black Book, which preserves early Welsh poems and stories even though nearly all the priory buildings have gone.
History checked 16 August 2026 against the named sources below.
A church record does not guarantee that the building or ground is open. Respect worship, burials, private land and current visiting rules.