The Sins On Their Bones by Laura R. Samotin

Set in a Jewish folklore-inspired reimagining of 19th century Eastern Europe, this queer dark fantasy debut pits two estranged husbands and a daring spymaster on opposite sides of a civil war. Perfect for fans of Leigh Bardugo, C.S. Pacat, and Katherine Arden.

Dimitri Alexeyev used to be the Tzar of Novo-Svitsevo. Now, he is merely a broken man, languishing in exile after losing a devastating civil war instigated by his estranged husband, Alexey Balakin. In hiding with what remains of his court, Dimitri and his spymaster, Vasily Sokolov, engineer a dangerous ruse. Vasily will sneak into Alexey’s court under a false identity to gather information, paving the way for the usurper’s downfall, while Dimitri finds a way to kill him for good.

But stopping Alexey is not so easy as plotting to kill an ordinary man. Through a perversion of the Ludayzim religion that he terms the Holy Science, Alexey has died and resurrected himself in an immortal, indestructible body—and now claims he is guided by the voice of God Himself. Able to summon forth creatures from the realm of demons, he seeks to build an army, turning Novo-Svitsevo into the greatest empire that history has ever seen.

Dimitri is determined not to let Alexey corrupt his country, but saving Novo-Svitsevo and its people will mean forfeiting the soul of the husband he can’t bring himself to forsake—or the spymaster he’s come to love.