The earliest life of St David dates from five centuries after his death, probably in 589. He became eminent as abbot and bishop at the site now known as St David’s, but formerly Mynyw, from which the present diocese of Cardiff-Menevia is named. He is credited with a monastic rule based on the example of the Eastern Fathers, and also with a Penitentiary. He was invited to preside at the synod of Llandewibrefi. Monks trained at his monastery evangelized South Wales and made foundations in Cornwall, Brittany and Ireland. St David is said to have sent a Mass rite to Ireland. At his death his contemporary St Kentigern, founder of St Asaph’s in North Wales, witnessed in vision his joyful entrance into the joy of his Lord. His holy relics have been found hidden in the fabric of St David’s Cathedral, where they are carefully preserved. He was canonized by Pope Callistus II in 1123. See the articles in the Catholic Encyclopaedia and Wikipedia/