Saint Deiniol was born in the early sixth century into a princely British family of the North. According to the Latin Life preserved in the Peniarth manuscript and transcribed in 1602 by Sir Thomas Williams of Trefriw, he was the son of the abbot Dunod Fawr, son of Pabo Post Prydain, rulers of lands in what is now northern England. When the family lost their inheritance, they were received in Wales and given land by Cyngen Glodrydd, king of Powys. Thus the young Deiniol learned early that earthly patrimony is fragile, and that the only kingdom which cannot be taken away is the Kingdom of God.
He renounced the world while still young and entered the religious life, studying, tradition says, under Saint Cadoc at Llancarfan, one of the great schools of Welsh monasticism. Some accounts place part of his early life in the solitude of a hermitage in Pembrokeshire, where he prepared in silence for the labors that would follow. Welsh tradition numbers him among the "seven blessed cousins," and records that he was called to the episcopate despite what were reckoned deficiencies in his formal learning — a reminder that God chooses according to holiness rather than reputation. With his father Dunod and his brothers Cynwyl and Gwarthan he is associated with the founding of the great monastery of Bangor Iscoed on the River Dee, a house so numerous that it later became famous throughout Britain, until it was destroyed by Æthelfrith of Northumbria about the year 616.
Leaving Powys, Deiniol went into Gwynedd, where Maelgwn Gwynedd granted him land and endowed his foundation with privileges. There he raised the monastery of Bangor Fawr — "Great Bangor" — on the strait of Menai, the site on which Bangor Cathedral stands to this day. The very name Bangor, from the wattled enclosure that hedged the monastic settlement, speaks of the humble beginnings of a house that became a renowned center of Christian learning, prayer and missionary outreach. Deiniol governed it as abbot, forming his monks in obedience, poverty and the steady round of the divine praises.
In time the see of Bangor was established with its boundaries corresponding to the principality of Gwynedd, and Deiniol was consecrated its first bishop. The traditions vary: some say Saint Dubricius consecrated him in 516, others that Saint David of Menevia, primate of Wales, ordained him bishop about 545 at the Synod of Llanddewi Brefi. He attended that famous synod alongside Saint David and Saint Dyfrig, where rules of penance were laid down and the Pelagian error was condemned — Deiniol standing with the fathers of the Welsh Church for the integrity of the faith and for the discipline that heals souls. Tradition holds that it was he who persuaded the reluctant David to come to the assembly.
Returning from the synod, he continued to plant churches: at Llanddeiniol in Dyfed, at Llanfor and Llanuwchllyn near Bala Lake, and in other places whose names still carry his own. He is remembered as a man of great holiness and simplicity, of prayer and healing, who gave himself to his flock as abbot and bishop to the end of his days. The Annales Cambriae place his death in 584; some reckon that this date, like those given for David and Kentigern, stands twelve years too late, so that he died in 572. He was buried, as was the custom of the Welsh saints, on Bardsey Island, the "island of twenty thousand saints," though tradition adds that his remains were afterwards carried to Bangor Fawr and laid in the cathedral consecrated in his name.
His cult spread widely through North Wales and beyond. Churches at Hawarden, Worthenbury, Marchwiel and elsewhere in Flintshire, at Llanfor, Llanuwchllyn, Eyton, Llangarron in Herefordshire and Itton in Monmouthshire bear his dedication, and the village of Llanddeiniol near Cardigan Bay is simply "the parish of Saint Deiniol." In Brittany he is venerated as Saint Denoual, and the parish of Ploudaniel in Finistère preserves his name. William Ewart Gladstone placed his residential library at Hawarden under Deiniol's patronage in 1896, and the hymn tune "St. Denio" — sung to "Immortal, invisible, God only wise" — may recall him. Both the Catholic calendar for Wales and that of the Church in Wales keep his memory on 11 September.
May Saint Deiniol obtain for us the humility that lets God build where he pleases, and let us imitate him today by giving some real part of our day to prayer and to the service of the Church we have received.
