In the best historical novels, history goes out of the window and love remains.

So it is in Rosemary Sutcliff's new novel "Sword at Sunset"—which is only theoretically concerned with King Arthur. As history, it is unconvincing. Miss Sutcliff's king has almost nothing to do with the familiar Arthur of folklore. She has reinvented him, given him a character of her own choosing and placed him outside the accepted legends altogether—in a closed world where nothing happens except at the dictates of her imagination. In this way—though the first-person narrator she presents is more mysterious than ever—he is somehow more credible than his legends.

This is not the Arthur of the history-books—the figure that scholars have puzzled over in the sparse chronicles of his time. At another level, he is not the central figure of [Sir Thomas] Malory's "Morte d'Arthur," or the more...