Another view, while accepting that "Owen" is a historical novel, sees it as "a marvellous blend of historicity and vision, of mythology and romance". But, as Canadian scholar W. J. Keith notes, "all three terms (novel, romance, and historical novel) have been employed and argued about" for nearly two hundred years, that is at least since the time of Walter Scott. He also makes the further point that such questions relating to genre are important if the intentions of an author are not to be "distorted". While Powys's starting point in this novel is the historical facts about Owen Glendower and the early fifteenth century, found in the works of historians such as J. E. Lloyd and J. H. Wylie, he also draws on legend, especially those relating to the mysterious disappearance of Glendower, and the idea that he was a magician. In addition Powys makes use of literature, including the poetry of Iolo Goch, Shakespeare's "Henry IV (Part I)", and Lady Charlotte Guest's "The Mabinogion", a collection of eleven prose stories collated from medieval Welsh manuscripts. The Welsh mythology of this latter work, especially the "Four Branches of the Mabinogi" (from which Guest derived her title), is particularly important in "Owen Glendower" and in Powys's next novel "". Jeremy Hooker sees "The Mabinogion" as having "a significant presence […] through character's knowledge of its stories and identification of themselves or others with figures or incidents in the stories". When Rhisiart, for example, first sees Owen Glendower, he remarks, "I'll be damned if he doesn't look like […] Pryderi!", while earlier, in Chapter Two, Tegolin remarks that when Rhisiart defended her he "looked like Pwyll […] riding against Halfgan […] King of Annwn. Indeed there are "almost fifty allusions to these four […] tales"' (The "Four Branches of the Mabinogi") in the novel, though "some that are fairly obscure and inconspicuous". Two thirds of Powys's allusions are from "Branwen, daughter of Llŷr", whose main character is Brân the Blessed, "Bendigeidfran", a giant and king of Britain, who Powys associates with the fortress of Rhisiart's ancestors, Castell Dinas Brân (though there is no known connection with the castle and this mythological hero).