Although initially banned, Christianity became the official religion of the Roman Empire. The empire's collapse in Britain created a 'Welsh' people whose identity has traditionally been based on Christianity and a common language.
Christianity arrived in Wales at the height of Roman power and was banned initially by the authorities who were suspicious of its secrecy and exclusivity. At first it was an urban religion, and the first Christian martyrs in Wales were killed early in the fourth century at the legionnaires' town of Caerleon.
However it soon became tolerated. The earliest Christian object found in Wales is a vessel with the ancient Christian symbol the Chi-Rho, dated 375 AD and found in the nearby Roman town of Caerwent. By the end of the 4th century Christianity became the sole official religion of the Roman Empire.
Gradually Roman power declined in Britain, until finally in 410 AD Emperor Honorarius advised the Britons to organise their own defences against the Barbarian threat. The only account to survive from this period comes from the Welsh cleric St Gildas.
Gildas wrote of the decline and ruin of Britain caused by its debauched and decadent rulers, with the pagan invaders being God's revenge for their spectacular fall from grace. The conflict, particularly with the Anglo-Saxons, created a process during the next two hundred years whereby a 'Welsh' people emerged out of the remaining Romano-Britons and native peoples, with their identity being chiefly based on a common religion and a common language.
By the time of St Augustine's mission in 597 AD to convert the Germanic tribes of south eastern Britain, Christianity was long established in Wales and other parts of western Britain, such as Cumbria and Cornwall. The earliest Welsh poetry dates from just before St Augustine set foot on Britain, and the poems of Taliesin and Aneirin's Y Gododdin bear testimony to the fact that Christianity was by then long established amongst the native British.
This period is usually called the 'Age of the Saints', a time of intense Christian activity in western and northern Britain and Ireland. Probably the most famous 'Welsh' missionary is St Patrick, who began the conversion of the Irish people. Ireland would later send out its own missionaries all over western Europe, and Patrick became acknowledged as the patron saint of the island.
In Wales St David, (Dewi Sant), became the pre-eminent Christian figure. He is the only native born patron saint of the countries of Britain and Ireland, a fact which speaks for the deep roots of Welsh Christianity by the time of his birth around the early sixth century. Before David there were other Christian figures in Wales such as St Dyfrig and St Illtud. They were followed by St Teilo, St Padarn and St Deiniol as well as St David.
Little is known about these people, but they must have been very influential because they gave their names to various places all over Wales, pre-fixed by the word Llan. For example: St Illtud - Llanilltud Fawr (Llantwit Major), St David/Dewi Sant - Llanddewi, St Padarn - Llanbadarn, St Teilo - Llandeilo. 'Llan' is an old Welsh word thought to refer to an enclosure of land, which early Christians needed to consecrate for burials as well as building a cell or church for worship.
Those who inspired such activity had the enclosure named after them. Many of these places are reputedly situated at older, pagan sites of worship, such as wells. There are literally hundreds of place names in Wales beginning with 'Llan', attesting to the industry of these early Christians. As well as place names, other evidence of the activities of the early Welsh Christians are the hundreds of standing stones to be found all over the country with Christian related carvings or inscriptions on them. Some carry bilingual inscriptions in Latin and Ogham, which arrived in Wales with Irish settlers at the end of the Roman Empire. Others have intricate carvings which have become characteristic of the Celtic identity, such as the cross at St Brynach's church in Nevern, Pembrokeshire.
Little remains in the way of illustrated manuscripts from Wales to compare with the wonderful designs to be found in the Book of Kells and the Lindisfarne Gospels, although it is believed that the Gospel of St Chad may have Welsh origins. It did spend some time in Wales at some time in its history, although it has been at its present location of Lichfield for hundreds of years. As well as two evangelist portraits of St Mark and St Luke, in its margins are found some of the earliest writings in Welsh, dating from the 9th century.
The eventual conversion of the Germanic tribes of England did not lead to a unifying of the Christian peoples of Britain under one organisation - which was the intention of the Papal mission led by St Augustine. Indeed, his approaches to Welsh bishops were firmly rebuffed in two meetings in 602 and 604 AD. Understandably the Welsh may have been unwilling to cooperate with a people which had disinherited them of the island of Britain, even if they had become Christian.
Later, there is evidence that Welsh and English Christians did find common ground as both nations came under attack from pagan Vikings from the late 8th century onwards. After dealing with the Danes in the late 9th century the great Saxon king Alfred set about improving learning in the English church, which had declined after years of attacks. He recruited a monk named Asser from the St David's monastery in west Wales. Asser became a close confidant of the king and his 'Life of King Alfred' is proof of the high standard of Latin used in the Welsh church. It is also an invaluable historical document on the life of a medieval English king.
It took Viking attacks to bring Welsh and English Christians closer together. It was to take the descendants of the Vikings, the Normans, to bring the Welsh at the point of a sword under the authority of the Archbishop of Canterbury.