The Seven Streams by Warwick Deeping

The book is a charming romance, where Deeping simulates a historical realism by depicting Arthur's world not as the chivalrous court of the late Middle Ages as found in Malory (followed by Tennyson and most nineteenth-century poets), but as the more appropriately rugged tribal society of the sixth century. Yet even this seeming realism soon yields romance, for the world of Deeping's novels depicts Roman elegance more than the crude realities of Saxon invasions and Briton resistance.