Y Gododdin is an extremely important text to Arthurian scholars because it contains the earliest known reference to
King Arthur in a context that can be considered historical. The consensus among historians is that the work must have been composed prior to A.D.
638, but no exact date can be fixed. There is only one reference to Arthur in
Y Gododdin, in a passage describing a leader named Gordur (Gwawrddur in old Welsh):
He charged before three hundred of the finest,
He cut down both center and wing,
He excelled in the forefront of the noblest host,
He gave gifts of horses from the herd in winter.
He fed black ravens on the rampart of a fortress
Though he was no Arthur.
This passage establishes that by middle of the seventh century at the latest there existed in Britain a conception of a historical figure named Arthur who was so greatly renowned that even a ruler who would charge 300 men cannot match up to him. The Y Gododdin is considered by many historians to be one of the most convincing pieces of evidence in favor of a historical Arthur, due to it’s early date, clearly historical conception of Arthur, and historically plausible content overall. Although some historians have questioned whether the reference to Arthur may have been added much later, there is no credible evidence for this view.
translation by A.O.H. Jarman