Catwg, variously known as Cadoc or Cadog, was born about AD 497 and died about 577. He was the grandson of Brychan, King of Brycheiniog (who gave his name to the former county of Brecon. Catwg’s mother was Gwladys, the third daughter of Brychan.
At seven years of age, Catwg was sent to Tathan’s religious seminary at Caerwent, lower down the Usk Valley, where he remained for 12 years. He founded this cell at Llangattock, apparently to evangelize the people around the encampment across the river as well as to commemorate his baptism in the Onneu Brook.
After his education, he resolved to follow the religious life, probably because of the early reckless and lawless life of his father and the encouragement of his devoted mother. He founded a monastery at Nant Carfan (later Llancarfan) which lies to the west of Cardiff and was destined to become one of the three monastic settlements in the Diocese of Llandaff.
Attracted by the force of his example, many of his former fellow-students at Caerwent joined him at Llancarfan. Although Llancarfan was large, it would not have been the mediaeval Roman-style of monastery most of us imagine. The religious communities founded by Catwg and his fellow Celtic churchmen were quite different. The ‘monks’ (we might better call them evangelists) lived alone, each in his small dwelling within a compound or ‘llan’ which was often a site of pagan worship that had been taken over for Christ, and they shared in the communal worship of their little church.
Several years later, Catwg continued his education in Ireland, studying at the school of Lismore under Carthagh, Abbot of Saighir, from AD 523 to 526. The last phase of his formal education was undertaken after returning from Ireland, when he settled in Llanspyddid to be instructed in Latin by Bachan, a celebrated Italian rhetorician.
In AD 527, tradition says that Catwg left Brycheiniog and returned to Llancarfan which he found derelict and uninhabited. He set to work with a will and a year later was able to hand the monastery over to Gildas while he himself embarked on a period of evangelistic travel. He visited Scotland, South and West Wales and Cornwall, and also travelled abroad, visiting Jerusalem three
times, Rome seven times and Greece.
During Catwg’s absence abroad, the famous Synod at Brefi (Llandewi Brefi) was held to settle some problems of church discipline. At this Synod, David was made Archbishop, and this occasion more than any other led to his being venerated as Patron Saint of Wales. But David had been reluctant to attend (he had to be summoned twice). His main reason seems to be that he believed that
Catwg should preside at the assembly because of his reputation for great wisdom. When Catwg returned to Wales he is said to have made a protest-fast, and only stopped when his uncharitable conduct was pointed out to him. About AD 564 David, Catwg and Gildas were called to Ireland to assist in reviving the Faith there. On his return a year later, the elderly Catwg found the management of Llancarfan beyond his powers, and so again handed over the monastery, this time to his disciple Elli, on Palm Sunday AD 575.
At this point the story of Catwg’s life becomes shrouded in mystery. All the written evidence for his life is of such a date and character that deprives it of almost all historical value. At the end of his life he became a bishop and took the name Sophias. His episcopate was short, for when he was celebrating Mass a Saxon horseman entered the Church and killed him with a lance. It is said that his last prayer was:
Almighty Lord, invisible king, Jesus Christ the saviour, grant me one grace: protect the Christians of my country and my monasteries.
Thus ended in martyrdom the life of one of Wales’ most honoured saints, to whose memory a number of churches in South Wales are dedicated. His body remained at Beneventum for a time and a church was erected over the grave. Eventually the monks of Llancarfan were allowed to remove it to the first monastery he had founded. His Patronal Festival is observed on 24th January, the date given in the eleventh century Exeter Litany, but in the Roman Calendar it falls on 25th September.