Lancelot du Lac, in metrical French, by Chrestien de Troyes, before
1200.

From these facts it is to be argued that the further back these
romances are traced, the more clearly does it appear that they spread
over the Continent from the North-west of France. The older
versions, it may be remarked, are far more simple than the later
corruptions. In them there is less allusion to the habits and usages
of Chivalry, and the Welsh names and elements stand out in stronger
relief. It is a great step to be able to trace the stocks of these
romances back to Wace, or to his country and age. For Wace's work
was not original. He himself, a native of Jersey, appears to have
derived much of it from the "Historia Britonum" of Gruffydd ab
Arthur, commonly known as "Geoffrey of Monmouth," born 1128, who
himself professes to have translated from a British original. It is,
however, very possible that Wace may have had access, like Geoffrey,
to independent sources of information.

To the claims set up on behalf of Wace and Geoffrey, to be regarded
as the channels by which the Cymric tales passed into the Continental
Romance, may be added those of a third almost contemporary author.
Layamon, a Saxon priest, dwelling, about 1200, upon the banks of the
upper Severn, acknowledges for the source of his British history, the
English Bede, the Latin Albin, and the French Wace. The last-named
however is by very much his chief, and, for Welsh matters, his only
avowed authority. His book, nevertheless, contains a number of names
and stories relating to Wales, of which no traces appear in Wace, or
indeed in Geoffrey, but which he was certainly in a very favourable
position to obtain for himself. Layamon, therefore, not only
confirms Geoffrey in some points, but it is clear, that, professing