Exiled from his see in Scotland, Kentigern is said to have founded a monastery called Llanelwy – which is the Welsh name for St Asaph – at the confluence of the rivers Clwyd and Elwy in north Wales, where after his return to Scotland he was succeeded by Asaph or Asa, who was consecrated Bishop of Llanelwy.

Early in the twelfth century Norman influence asserted itself and in 1143 Theobald, Archbishop of Canterbury, consecrated one Gilbert as Bishop of St. Asaph, but the position of his successors was very difficult and one of them, Godfrey, was driven away by poverty and the hostility of the Welsh.

A return made in the middle of the thirteenth century (London, British Library, Cotton Vitellius, c.

Dedicated to St Asaph, it was a plain massive structure of simple plan, and was again destroyed during the Wars of the Roses.

Redman was abbot of Shap Abbey and visitor for the Premonstratensian canons, and spent most of his time visiting their monasteries or his diocese; he was diligent in his duties and felt no need to be resident in the city.

The last bishop in communion with Rome was Thomas Goldwell, who acceded in 1555 and was in the process of being transferred to Oxford when Queen Mary died and Elizabeth I came to the throne.

The Report of the Commissioners appointed by his Majesty to inquire into the Ecclesiastical Revenues of England and Wales (1835) found the see had an annual net income of £6,301.