Like other "historical" takes on the Arthurian legends, the series postulates that Post-
Roman Britain was a difficult time for the native Britons, being threatened by invasion from the
Anglo-Saxons in the East and raids from the Irish in the West. At the same time, they suffered internal power struggles between their petty kingdoms. Like
Marion Zimmer Bradley in her novel
The Mists of Avalon, Cornwell also presumes friction occurred between the old
Druidicreligion and
Christianity.
The story is written as if it took place in
Dark Age Britain as described in the original Welsh legends, with appropriate types of technology, culture, warfare, and attitudes. Cornwell also weaves later additions such as
Merlin and
Lancelot into the plot.
The
protagonist of the series is
Derfel Cadarn (pronounced Derv-el), based on the part-legendary
Saint Derfel. Cornwell's Derfel is a Saxon brought up as a Briton by
Merlin, the greatest of all Druids. In the course of the story, he becomes a great warrior and one of Arthur's warlords in his war against the Saxons. Merlin, meanwhile, concerns himself with trying to restore the
old gods of Britain. Other characters from the Arthurian mythos are given significant and memorable twists. For example, Lancelot, always portrayed as the most virtuous and the mightiest of Arthur's knights, here is depicted as an arrogant, cowardly and self-serving petty prince, whose legendary feats and martial prowess are crafted through the songs of the bards and a fictional reputation that he himself carefully cultivates.
Sagramor is a Hungarian prince in the
Lancelot-Grail Cycle, but is depicted here as a
Numidian veteran of the old Roman Army who joined Arthur's service after the collapse of the Empire. Cornwell portrays Merlin as a lecherous, driven, mischievous and irreverent druid.[
citation needed]
Also interesting is his solution to the problem of integrating the
magic of the Arthurian mythos in the context of historical fiction: he leaves room for the reader to take the "magic" depicted in the story at face value or to interpret it as a mixture of coincidence, psychology, primitive technology and illusion which preys on the superstitions, religious fundamentalism and intolerance of the time