I am not a great fan of Harry Turtledove's books, although perhaps that is just due to only having read a few of them. I read his Atlantis series, but I also indulged in the plot summaries of the War that Came Early and of course, his famous TL-191 Southern Victory series, and much of Turtledove's work seems to either exactly replicate the world, but in an alternate reality (such as Atlantis, which mimics the development of the United States precisely save for it being detached from the rest of North America), or mirror it, such as his TL-191, or the War that Came Early, as he reversed history and made their timelines the exact opposite of what happened historically, without any more complexity. Allies lose WW1? They go fascist and are modeled on the Nazis, and launch a campaign of revenge! The South loses the war? They end up exactly like the revanchist Germans! Even when he tries to create his own plot twists in The War that Came Early, it is terribly implausible and bizarre, such as the constant side flipping of the French and entire army group defections. With such a dour introduction, you can see why I found it surprising that his work "Agent of Byzantium" is such a radical departure and shows why Turtledove really is a revered writer of alternate history, as he has created a story with excellent characters, particularly its main spy character Argyros, a fascinating point of departure, brilliant sense of wit, tragedy, excitement, a feeling of realness, and a real feel of "mise-en-scène and authenticity, giving the Roman/Byzantine Empire and its neighbors of a universe where Mohammad never died and the Romans survived a plausible and real-feeling path, history, and destiny.
This is particularly evident with the effort which Turtledove has paid to the traditions, customs, styles, cultures, of the Byzantine/Roman Empire and beyond. Little touches about the imperial bureaucracy and their love affair with paper work (including 7-centures long property rights battles), the Egyptians and their love of litigation, stereotypes of the empire's inhabitants, accents, languages, the distribution of religions, be it in the "heretics" of Egypt and Palestine or the different prayers of the Franco-Saxon kingdoms - they give it a definite feeling of realness, make the Empire breath like it is a living entity. The theological elements, with conversations between Argyros and Jurchen/Angeland barbarians over theological discussions, the eternal entertainment of the Byzantines, is one of the best signs of how much work Turtledove put into researching the history of Byzantium and its religious disputes. Historical citations - from Saint Gregory of Nyssa is drawn the following and repeated by Argyors about the people of Constantinople and their theological musings - If you want a man to change a piece of Money for you, he informs you of in what the Son differs from the father; if you ask the price of a loaf, you’re told by way of reply that the Son is inferior to the father ; and if you enquire whether the bath is ready, the answer is that the Son was begotten out of nothing.’’ complete it with a sense of historical grounding, and Greek words scattered throughout for theological or labor terms provide a real sense of immersion.
True, Turtledove has posited a very conservative direction for the Eastern Roman Empire - in the sense that it has evolved much slower, internally, than historically. Its structures of administration and governance look much like those of the early years of Byzantium, perhaps even earlier than the point of departure in the early 7th century, despite the nearly a thousand years (sometimes difficult to remember, since Turtledove, in another quirk, uses the Byzantine system of dating since their presumed creation of the Earth, thus placing the story in the 65th century rather than the 14th). But he purposefully and deliberately wrote it in this way and admits it as such. I don't hold it against him, and the Byzantine Empire that he has constructed feels real enough that it doesn't hold back the book.
The best part of Agent of Byzantium is its brilliant set of characters. Of course, it is very strongly focused on Argyros - since it is a short story collection, he naturally must be the main character who leads it along, although the Persian agent Mirrane also joins him as a repeating individual. But beyond Argyros, the book has a real talent in making even short encounters with garrison commanders or bureaucrats give a real glance on their personality and make them feel alive. Argyros himself is an immensely satisfying main character, witty, intelligent, brave, but with his bouts of superstition (to us, for a man of the time perfectly normal), and hiw own tragedies and weaknesses, those for women particularly. He isn't perfect, although he comes too close to being so, and the genuine contrition he feels after a fling with a prostitute , makes him more balanced and less cliched. Argyros is an excellent center of the story, around which the rest revolve.
I also find the way in which the Empire is portrayed, as being less innovative in technology than its neighbors, is a realistic, balanced, and interesting compnent, and one which gives added depth to the book. We see the Empire from the inside, and not from without, and what a country it must be between what are clearly fast advancing surrounding states, inventing the printing press, gunpowder, the telescope - while the Romans appear essentially inventively stagnant, complacent, and stuck in their ways, only really producing brandy on their own as far as inventions go. They rely upon clever and sophisticated agents like Argyros to provide the skies and explorers to keep the empire afloat. Strong, mighty, great, splendid the Roman Empire might be, but also placid and over-confident.
The one thing which I seriously object to in the book is that Argyros, the main character, is too successful and effective. I wouldn't go so far as calling Argyros a "Mary Sue," since he does have serious flaws for pleasures of the flesh at least, but overall Argyros comes up with solutions and ideas that he should by no rights have the capability to do. Consider him in the section on the Iconoclasm dispute in the Byzantine Empire, where it is him who suggests the critical theological debate that enables the Iconophiles to resist the Iconoclasts - Argyros is a smart man, and decently educated on theology, but how is it that he is the one who sees the argument made about icons being made to represent Jesus's human side when far more theologically astute and capable men are around? The rest of the book can be explained away by luck, fortune, and Argyros being in the right place at the right time, as well as the short-story origin of the book which is a compilation of short stories, but Turtledove would have done well to include an additional story where Argyros definitively fails at one of his missions or shows a crucial flaw, instead of his mostly constant successes in the book.
Agent of Byzantium joins other famous Roman/Byzantium alternate history legends such as Lest Darkness Fall in creating a rich, lovingly crafted story of a different Rome, one imbued with an American optimism and hope which somehow works with the story rather than clashing with it. It has wonderful and satisfying characters, dashing and thrilling adventures, a bold and fast style of writing: it is a perfect book for anyone who is a fan of thrill and excitement, daring and dash, and the eternal and romantic saga of Rome.