Anonymous, Welsh Triads — from the Red Book of Hergest
“ Caswallawn son of Beli until the time of Custennin the Blessed, Arthur's grandfather. This is the answer that Arthur gave to the emperor's messengers: that the men of Rome had no greater claim to tribute from the men of this Island, than the men of the Island of Britain had from them. For Bran son of Dyfnwal and Custennin son of Elen had been emperors in Rome, and they were two men of this Island. And they Arthur mustered the most select warriors of his kingdom (and led them) across the sea against the emperor. ”
