This is by Harry Turtledove, set in his Videssos universe. It's the third book in the Krispos series and whereas the first two books look at Krispos as a young man on the rise, in this book Krispos is well into his middle years and fairly secure on the Throne but faced by one of the more subtle threats to that rule. The Thanasioi preached the rejection of the physical in favour of the purely spiritual and their rejection of the overwhelming wealth of the official church earned them many converts in the poorer classes of Videssos but religious dissention could get out of hand with less reason and religious civil wars are amongst the least pleasant versions of war. Not only does Krispos have to worry about the present but the future is looming large as he has to decide whether to trust his eldest son (possibly!) as the successor, or wonder whether his second son, who'd won kudos with the army while on campaign and with the citizens of the capital as he helped put down Thanasioi inspired riots would do something to rectify his lesser position in the succession.

Now, as I might have mentioned at the top of this review this is by Harry Turtledove and if you know much about the Eastern Roman Empire, you may find a few echoes here and there in these works and this is because Harry Turtledove is also Professor Turtledove whose area of specialisation is Byzantium History. Rather neatly, these echoes aren't too overwhelming and he also manages to keep the cast of characters down to a reasonable number, not something he always manages to do. :-) ( )

This is the last in the farmer-turned-Emperor series of Videssos books. I don't know if this is loosely based on real Roman history or not, but it seems like considering the author's tendency to do that. It always seems if the Empire is on the verge of disaster, going from one crisis to another. Maybe that was historically normal, but it makes the books feel a bit chaotic. Good, but not great. ( )