>>On the subject of Celtic derived works - who knows something about the
I checked a couple of books and haven't found much about them.
One source says that they were nothing more than mendicant lay clerics, a
bit like the Third Order of St. Francis today. They began to appear some
time in the sixth century in Scotland and Ireland.
The other source, which is on Irish Druids and early Irish religions (sorry,
don't have the ref. with me) is of the opinion that although they were
Christian they retained much Druid lore which they incorporated into
Christian teaching. They may have been responsible for what is now termed
the 'Celtic church', as distinct from the Latin church. Giraldus was
particularly scathing in his comments about them.
They were strongly associated with the Picts and seem to be best known as a
Scottish sect. St. Columba of Iona is thought to have been a Culdee and
Iona may have been a Druid school before it was Christianised. They are
also known from Ireland - I didn't see any mention of Wales.
A number of interpretations have been put forward for the name but the most
favoured is Ceile De/, meaning Servant of God.
Hope this helps a bit.