A HistoricalFantasy duology by Canadian author Creator/GuyGavrielKay, consisting of:

* ''Sailing to Sarantium'' (1998)
* ''Lord of Emperors'' (2000)

Set in the same world as Kay's earlier novel ''Literature/TheLionsOfAlRassan'' and his later ''Literature/TheLastLightOfTheSun'' (and thus, by extension, in the same universe as ''Literature/TheFionavarTapestry'' and ''Literature/{{Ysabel}}''), but in a different time and place, "The Sarantine Mosaic" is the story of (or at least, the story surrounding) one Caius Crispus, a mosaicist dwelling in Varena, Batiara (which is [[FantasyCounterpartCulture in no way Ravenna, Italy]]). Dispirited by a plague that killed his wife and daughters, Crispin soon finds himself accepting a commission meant for another man that will take him to [[strike: Byzantium]]Sarantium, as well as being given a secret mission by the imperilled queen of Batiaria meant only for the ears of Emperor Valerius II. Crispin's adventures overland will involve gods, armies, an incredible array of potential {{Femme Fatale}}s, [[ArsonMurderAndJaywalking and lots of chariot-racing.]]

The duology is based on the history of the reign of the great Byzantine Roman Emperor Justinian I and his wife Theodora.

!! Tropes featured include:

* [[spoiler:BittersweetEnding]]
* ChariotRace: A major subplot revolves around racers.
* TheChessmaster: Many characters play at this, Valerius II most of all. [[spoiler:But even he can be surprised...]]
* CruelMercy
* DemotedToExtra: Some characters who were fairly prominent in the first book don't get much play in the second.
* FantasyCounterpartCulture:
** Sarantium = Byzantium/ Eastern Rome
** Bassania = Sassanid Persia
** Batiara = Ostrogoth Italy
* FemmeFatale: Styliane.
* GreyAndGrayMorality: Some characters are less likeable than others, but it's hard to say that any of the major factions are totally in the wrong.
* HistoricalFantasy
* LaserGuidedKarma: [[InvokedTrope Invoked]] by [[spoiler:the Dalenoi conspiracy to kill Valerius II in the same way he killed their father, though he's actually dead before the Sarantine Fire is used, as it turns out.]]
* LoadsAndLoadsOfCharacters: The cast is pretty big in the first book, and balloons even more in the second.
* LowFantasy
* NoCelebritiesWereHarmed: Where to begin?
** Valerius I = Justin I
** Valerius II = Justinian I
** Aliana/Alixana = Theodora
** Leontes = Belisarius ([[CompositeCharacter with a bit of Heraclius]] for good measure)
** Styliane = Antonina
** Shirvan = Khosrow II Parvez
** Pertennius = Procopius
** Ashar ibn Ashar = The Prophet Mohammed
* NotHisSled: Readers familiar with the history of the reign of Justinian I will note that things diverge markedly from the historical record about when [[spoiler:Justinian/Valerius is assassinated, resulting in Belisarius/Leontes being proclaimed Emperor and not going to fight a war in Batiara/Italy]]).
* PsychoForHire: Valerius II's former chief tax collector, the most efficient man to ever occupy the post, so long as you overlook his [[DepravedBisexual sadistic private activities.]]
* RescueRomance: Teased but averted.
* RewardedAsATraitorDeserves
* SecondLove: The duology could be described as Crispin sorting through the numerous candidates for this status. [[spoiler:And, as it turns out, Alixana too.]]
* SeriousBusiness: Chariot racing. TruthInTelevision, from the historical record.
* ShownTheirWork: Guy Gavriel Kay clearly spent a lot of time reading up on mosaics and chariot racing.
* SpannerInTheWorks: [[spoiler:Everybody forgot about Gisel...]]
* SupportingProtagonist: Crispin is the closest thing to a main character, but he's often more an observer than anything else.
* UnwittingPawn: [[spoiler:Leontes]] is supposed to be this for [[spoiler:the Dalenoi, but things don't quite go according to plan.]]
* WackyWaysideTribe: The chariot racing, arguably.
* XanatosSpeedChess