Talesin the 6th century Bard wrote
https://en.wikipedia.org/wiki/Taliesin"“Christ, the word from the beginning, was from the beginning our teacher, and we never lost his teaching. Christianity was in Asia a new thing; but never was a time when the Druids of Britain held not its doctrine”"
There are no conflicts recorded anywhere between the Druids and the Christians, in fact the first three Arch-Bishops of the Celtic Church were all Arch-Flamens of the Druidic order, as their fathers had been before them. To be a Druid was a hereditary position, the same as to be a Levitical priest or a Brahmin was. This hereditary title to priesthood was still being followed by the British Church right up until the twelfth century, long after the Church at Rome had become corrupted by ‘democracy’ and ‘equality.’
The Druids were awaiting a Messiah, followed a similar law to Moses and referred to the coming saviour of the future as Yesu.
There was a "supreme god" whose name has been lost to time. This supreme deity was represented by a trinity of three deities, each representing a different aspect of this god: "Teut," "Bal the black," and "Kor."