Religion is one of those things one is not supposed to talk about in polite company, but thankfully books have no such obligation. Heart of Iron is not specifically about religion, but religion does play a role. The Crimean War is interesting to me because in it a Christian nation (England) allied with the Ottoman Empire against another Christian nation (Russia). Alliances and wars are drawn and fought along religious lines more often than not, so that seemed like a curious case, perhaps signaling that in the modernized world, politics and economic interest would overrule old-fashioned superstitions. On the other hand, considering the number of foreign invasions Russia had undergone, it apparently was considered sufficiently alien -- and while I don't want to go into the whole Byzantium vs Rome thing, Eastern Orthodoxies seemed to have been a direct opposition to Romanized west.
Anyway. Since in Heart of Iron Russia is undergoing rapid industrialization, it seemed reasonable that religion would be pushed back a bit, and the Orthodox Church would have a little less political prominence. So Sasha is religious but not terribly devout, and she isn't the type of person to question her religious upbringing much. I mean, cross-dressing and university seemed unconventional enough; making her an apostate on top of it would've been a bit much.
On the other hand, I could not abandon religion entirely, since the Taiping rebellion features prominently, and it was based on Christian heterodoxy: Hong Xiquan believed himself to be Jesus' younger brother. In the bibliography section, there's a link to Hong's biography, God's Chinese Son -- a fascinating book of a fascinating life. And as far as I was concerned while writing Heart of Iron, the fact that the Taiping were Christians created as much of a barrier as a facilitation in making their (fictional) alliance with Russia. After all, shared religions can be quite helpful in finding common ground; and yet common religion differing in some details (as in pretty much any Christian branch) can be profoundly dividing.
Additionally, I feel that the fact that Hong claimed to be God's son (and thus the younger brother of Jesus) was especially tainted by no small amount of racism: while self-proclaimed prophets and messiahs are not uncommon, those who are critiqued the harshest are the ones who are perceived as having the least right to such claims. With doctrines of racial superiority quite dominant in Europe at the time, I suspect that the idea of God having a non-white son was particularly scandalous.
Of course, I couldn't be satisfied with a mere conflict between Anglicans, Russian Orthodox and Taiping Christianity. I enjoy diverse religious landscapes, and so in the book you will hear from a variety of viewpoints - from traditional Chinese religions, to some Norse beliefs, to downright heresies. Cornet Volzhenko, for one, is the follower of the charismatic Rotmistr Ivankov. Not to give too much away, but there is one Hussar regiment in the book which does as much (or more) philosophizing as fighting, and they are as liberal with their religious influences as I am with history.
So here's a teaser:
“Valhalla,” the rotmistr said and sobered up visibly. “Not because of what you think, Menshov—not just weapons or the flying wenches . . . whatever they are called.”
“Valkyrie,” Petrovsky offered in a reverential tone, his eyes glistening. I guessed that he harbored some ideas of his own as well.
“Right,” the Rotmistr said, nodding. He pulled a wine bottle from under the bench where it fit for easy storage, and topped off the mugs of both cornets. He handed the bottle with the leftovers to me, and I guessed that I was to drink directly from it. “But flying wenches or no, this is not why. You know that in the great hall, in Odin’s hall—and Odin is the one who takes the warriors fallen in battle—they drink and then they fight, and whoever falls in that battle wakes up whole again, so he can drink and fight and die again. In Valhalla, it’s not like heaven, where you get to stay alive forever and play some lute or harp . . . there, the world is destroyed every day, and then rebuilt anew, so nothing is ever old, ever stale.”
I took a cautious sip of the wine. “But everyone gets resurrected and they’re still the same.”
The rotmistr wagged his thick, calloused finger at me, dirt around his fingernail black as gunpowder, and I suspected that it had become incorporated into his skin and could never be washed out. “No one is the same after resurrection. Read the classics, Menshov. Cannot step twice in the same river, and everything changes even if you go away from home for a week. What do you think happens to everything, to the world, if you daily destroy and rebuild it? It changes, because nothing can ever be recreated perfectly.”
“So what do you want with it?” I asked, wine making me bolder. “You want to be killed and resurrected too?”
He shook his head, sly. “No no. I’d sit in the corner and watch and take notes, on how everything becomes different from day to day to day. I would keep track of all the small alterations, of all the tiny fault lines and cracks that appear from one resurrection to the next. And I will be there when everything finally crumbles to dust.”
And here you have it. This book is by no means a study in religion, but I hope that I sketched in enough of it to give depth and verisimilitude to people and their beliefs.