Historical fiction has been on the upswing in recent years, but very little has been set in Russia, let alone Siberia. What gave you the confidence, as a Scotsman, to do it in The People's Act of Love?

I did live in Russia for a third of my adult life—I'm now 42. That's enough time for a large part of your soul to be invaded by it. But I tried to get away from the kind of historical fiction where a writer takes a remote location, in time and space, and puts it in a brass box so people can peer in and enjoy the spectacle. With my fiction, I would like them to go to the box and find that a hand comes out and touches them on the shoulder. My book is really about humans facing an extreme version of an eternal situation that happens to be set in 1919.

The plot involves a sect of castrated Christians, a cannibalistic ex-convict and a legion of Czech soldiers marooned after the revolution, all of whom are grappling with religious or political idealism. Where did it start for you?

In Moscow, there was a Russian assistant in the Guardian bureau where I was working who mentioned it was just the time of year that prisoners [used to] escape from camps in Siberia. They would take a naïve prisoner with them as a walking, packed lunch. Without consciously bidding it, I imagined two men walking in the forest: the one knowing he would kill the other, and the other beginning to suspect it. While this was fermenting, I heard about the stranded Czechs and the castrated sect. As I wrestled with putting them all in one book, the character of Anna came to me as the one around whom these tormented men would revolve.

As a full-time journalist, often covering military conflicts, how did you find the time to write your novel?

In 2003, when I went to cover the invasion of Iraq, I spent so long working—from 7 a.m. to 10 p.m., seven days a week, for weeks on end—that I had a lot of time off [due to me] when I came back. Instead of taking a holiday, I decided to go to an isolated place and write.

Was writing fiction a way to distill your wartime experiences in Iraq and in Chechnya before that?

It's not a release to write a novel after being in a war, on a conscious level. The book is set in war's aftermath, but it's more about human relations on the most intimate level, and the dangers of idealism in love. The truth is that right now, I'm carrying more scars from the field of love than the field of war.