While each of the books in Stevenson's trilogy can be read on its own, this last offers a richer experience if read in the context of the other two. The first volume, "The Winter Queen," set in the 1600s, chronicles the relationship between the former Queen Elizabeth of Bohemia and Pelagius, an African prince kidnapped and sold into slavery, but free at the time he meets Elizabeth. They married secretly and had a son, Balthasar, whose life is the subject of the second book, "The Shadow King."
"The Empress of the Last Days" takes place in 2002. It involves a circle of European academics who come upon a trove of 17th century papers in Holland, including a theological journal by Pelagius and his catalog of West Indies plants and their uses. The rest of the papers include a never-before-seen play by the English writer Aphra Behn, and a miscellany of papers from a printer, Petrus Behn, who seemed to specialize in political satire and pornography for an English clientele.
Corinne Hoyers, the Dutch Ph.D student who first reviews the papers, has no idea how these items came to be jumbled together, but readers of "The Shadow King" will know that Aphra Behn, wife of Petrus, stole Pelagius' books from Balthasar. Corinne turns over the Aphra Behn material to a young Oxford don, Michael Foxwist, who subsequently discovers Pelagius' marriage certificate and Balthasar's baptismal record hidden in the binding of one of Pelagius' books.
Being English, he instantly sees the significance of this - Elizabeth Stuart's legitimate male heir should have inherited the throne of England - and the succession should never have been diverted to the Windsors, current holders of that chair. As Britain rather half-heartedly gears up to celebrate the present Elizabeth's Jubilee amidst the latest wave of scandals and tawdry gossip, Michael discovers a more legitimate heir - a young black female scientist in Barbados.
Michael does not, incidentally, share any of this - from the discovery of the documents to his meeting with Melita Palaeologue, the rightful heir - with his Dutch colleagues on the project. When he does finally get around to telling them of his discovery, they are not in the least perturbed, which strikes one of the book's few wrong notes. Stevenson may be trying to make the point that the British royal dynasty is of interest only to Britons, but our own tabloids can attest the to the speciousness of that claim.
Besides, Stevenson has been at pains to point out that academics are a cutthroat lot, in fierce competition for prestige, jobs, money and important finds. Documents challenging the succession of the major reigning European monarchs are good for all of the above. And a man who would keep such a secret from his colleagues would sound alarm bells of mistrust to an already paranoid confraternity.
Melita, a plant biologist, also remains unimpressed with her claim to royalty. From her point of view, "this whole idea's almost like an insult. In terms of genetics you can't say one bloodline's important and none of the others count." Though Michael agrees when she points out that 90 percent of her ancestors are African, he can't help but point out that Pelagius was an African prince and on the Palaeologue side - 17 generations back - she's a descendant of the last Emperor of Byzantium.
A subplot - the obsession of Michael's dotty uncle - makes Melita the "Empress of the Last Days," a prophesied messiah-like regent, too confusing to recount here, but showcasing the mystical, almost fairy-tale trappings people confer on descent - ignoring the thousands of superfluous or undesirable ancestors.
Melita and Michael fall in love. Stevenson handles this with passionate delicacy; they are cautious people of different backgrounds, interests, attitudes, and ambitions. But Michael is going back to England and they don't have a lot of time. And Melita must decide whether her right to the throne is the moral imperative Michael thinks it is.
Like the previous two novels, this one is deliberately paced. Stevenson is not shy about diverting the unfolding plot with a discussion of Oxford's duty to tradition and the modern student, or the relevance of royalty to history and society's present concerns, or various issues of race, privilege, tradition and academia.
A page-turner in its leisurely way, this is a fine conclusion to an absorbing, very different trilogy of ideas, romance and history.