Poetry, as well as prose, came strongly under the influence of the church. Clerics were the copyists of the manuscripts in which poetry was preserved and, as such, could act as censors as well as conservators. The church had a vital role to play in the process of educating the poets. Poetry was regarded as a part of grammar, for “grammar was the mother of all arts” [Peniarth]. But grammar could be learned only from the church, in whose schools it was the basis of all education imparted. So, if the Welsh poets wished to have themselves considered men of culture, to be raised above the level of common jongleurs, they must acquaint themselves with the art of grammar as it was taught in all the schools of Christendom. Thus, it came about that the poets, few of whom understood Latin, were dependent on Welsh adaptations of the grammar of Donatus, the dwned, as it was known in Welsh. It is significant that the first of the poetic grammars known to us is that associated with a priest, Einion Offeiriad (“Einion the Priest”), a work which was probably compiled between 1322 and 1327.
From: The Welsh Church from Conquest to Reformation by Glanmor Williams; 2nd edition (Cardiff: University of Wales Press, 1976), p. 106. The first edition was published in 1962.