While Geoffrey of Monmouth may surely be credited with producing the first ordered, sequential, and complete Arthurian story, that story quickly moved from the realm of Latin history (or pseudo-history) into the world of vernacular romance and chronicle adaptation. By the end of the twelfth century, we see the romances of Chrétien de Troyes and the vernacular adaptations of Geoffrey in Wace's Brut and in the Welsh Bruts; by the thirteenth there are Layamon's translation and adaptation of Wace, the Welsh adaptations of French romances, and the great French prose cycles. The few free-standing Latin Arthurian narratives studied in the chapters that follow seem slight next to this vernacular proliferation. It would however be misleading to suggest that they are the only evidence for the prominence – or lack of it – of the Arthurian story in Latin prose and verse.

There is a wealth of Arthurian reference in Latin chronicles, both before and after Geoffrey. Before Geoffrey, Arthur appears (perhaps) as the unnamed victor of Badon in Gildas, as the dux bellorum of “Nennius,” with his list of battles, and the Arthur who died at Camlann with Medraut in the Annales Cambriae. Also before Geoffrey's Historia is the famously disgruntled remark of William of Malmesbury in his Gesta Regum Anglorum: “This is that Arthur about whom the foolish tales of the Britons rave even today; one who is clearly worthy to be told about in truthful histories rather than to be dreamed about in deceitful fables, since for a long time he sustained his ailing nation, and sharpened the unbroken minds of his people to war.”