THESE TWO NOVELS cover, between them, the

dynastic struggles of 11th-century Britain. The Breath of Kings is concerned with England from the death of Ethelred through the reign of Edward the Confessor to the eve of the Norman Conquest of 1066. King Hereafter is a labyrinthine chronicle of the life, conquests, ambitions, and ultimate defeat of the Orkney Islands chieftain Thorfinn--who, Dunnett asks us to assume, was to become known to the history and legend of Scotland and to the literature of England under his Christian name, Macbeth. (The awkwardness of this sentence will be explained hereafter.)

The margins of the two stories, like the borders of the two kingdoms, are entangled--Macbeth appears briefly in Farrington's book, and Canute and Edward are powers offstage in Dunnett's. Beyond this, however, the books have extraordinary similarities, in their seriousness of intention and approach and in their attitudes toward history. Neither, mercifully, is an instance of the ripped-bodice historical best-seller. Indeed, their single flaw is a shared one. Sex is approached warily and unsteadily, Dunnett leaning toward a dreamy lyricism ("like the blazing white wand of a goldsmith. Half-returned, her body vibrated . . .") And Farrington toward a rough and lugubrious literalness. Quite to the contrary, these are books obsessed, as all serious historical novels must be, with history itself, with the past as past.

The two novels unfold chronicles of an almost awesome complexity, and they make very few concessions to whatever degree of historical ignorance the reader may be laboring under. And this is likely to be considerable. Most historically educated readers will know, in a quite general way, that in 1066, Harold the last Saxon king and William the Conqueror each held claims upon the English throne which were, in different ways, questionable. And to know also that in that fateful year, Harold had first to march north to fight Harald Hardrada, then hurry south to confront William's invasion. They may also know, perhaps hazily, that these circumstances had come about because kingship in 11th-century England was a very untidy business, with what Farrington rightly calls "the great houses of the North" intricately involved with one another through marriages, claims, feuds, alliances, and betrayals. And if circumstances in England are calculated to bewilder the modern reader, they are clarity itself as compared with the situation across the border in Scotland.

Dunnett and Farrington are aware of the problems which confront them. The novels are furnished with elaborate genealogical tables, populated by what seem at first to be less names than simple agglutinations of rough syllables--Ligulf and Walteof, Elfgifu and Sven the Forkbeard. Other than these tables, their common procedure is to fling the reader into the midst of half-comprehended events, into unfamiliar and semi-barbarous societies, and then leave him to sort matters out for himself as best he can, with little explicit authorial assistance. The procedure is, in each instance, a deliberate artistic choice.

In dealing with the past, and especially a past as remote as the 11th century, a historical novelist has, basically, two choices. He can simplify drastically--simplify the historical situation, the society, the rich entanglement of fact as this has come to us in document or chronicle or legend. And, especially, he can simplify by endowing his characters with attitudes and beliefs which are our own, rather than those of his remote world. This is the course taken by most poor historical novelists, prompted either by ignorance or by ineptitude. But also by several of our very finest. Mary Renault's Alexander trilogy, for example, is shaped upon the principle of simplification, although she has found her own means, through the use of mythic resonances. The other course, that taken by Dunnett and Farrington, is that also of what often seems to me the one great historical novel of our age, H.F.M. Prescott's The Man on a Donkey (1952).

Despite their choice of method, however, neither novelist has written a mere chronicle. The welter of historical detail in The Breath of Kings is so shaped and organized that two contrasting figures come at last to stand forth-- Emma, the wife of first Ethelred and then Canute, and her son Edward, the strange, moonstruck, perhaps saintly man who at last becomes king, and passes into history as "the Confessor." In King Hereafter, of course, it is Thorfinn/Macbeth and his strong-willed wife, Grua, who dominate the action. Dunnett imagines him as an alert, intelligent, and supple tribal chieftain, caught between the pagan world of the Vikings and the Christian world spreading from the south. In a sense, the novel can be seen as a struggle, muted and inarticulate, between Thorfinn/Macbeth's intelligence and ambition, and the overwhelming counterweights of a society as yet too inchoate to accept the coherence of political unity.

Novels such as these can prompt questions not only about themselves and their authors, but about their readers. Do we enter such pasts as these because they offer colorful paradigms of the present, assuring us that such passions as the will to power transcend history, that people have always been pretty much the same? Or are we attracted to the past precisely because it seems so profoundly different from the present, a barbarous world, no doubt, but one in which the deepest passions can discover channels of gratification? These questions have been with us ever since Walter Scott invented the historical novel, and the 19th century invented the historical imagination.

But now I must pass from these very general questions to a very particular one with which Dunnett has presented us. As I have said, she would have us to believe that the Orkney chieftain Thorfinn became king of Scotland and passed into history as Macbeth. But history, at least such Scottish history as I am familiar with, has always told us that Thorfinn and Macbeth were two quite different people. It was Thorfinn, the Norwegian earl of Orkney, who defeated King Duncan in battle, but it was Macbeth who killed Duncan, later, and then claimed the throne, basing his claim upon the connection to the royal family of his wife, Grua.

Dunnett, that is, either has reason to believe that history has confounded the two men, or else she has herself conflated them into one. And their wives as well, for her Thorfinn/Macbeth has a wife named Ingeborg who is known as Grua, but conventional history tells us that Thorfinn had a wife named Ingeborg, and Macbeth a wife named Grua. It well may be that what she has done has been to correct conventional history. The dust-jacket tells us that she "has made luminous use of the immense research in archeology and linguistics." And her earlier historical novels, dealing with a later period, display a formidable and disciplined knowledge of Scottish history. But one way or the other, a brief prefatory historical note, setting forth the facts, might have been of great help to the reader.

The Macbeth of literature, a creation of Holinshed's chronicle and Shakespeare's imaginative genius, has only the sketchiest of relationships to historical fact, but he is unlikely ever to be supplanted. The Macbeth of history has been wandering for 900 years, in Highland mists and across the treacherous, quaking bogs of half-known facts. Dunnett has done a splendid work of restoring his world, its colors, textures, sounds, the look of its seacoasts and mountains, the ways in which men measured their wills and strengths and their booty, one against another. I wish only that she had found a way to make me absolutely certain that in restoring the man's world, she did not make the man himself "disappear," retaining his name and bestowing it upon another.