Swedish author Natt Och Dag makes his debut with The Wolf and the Watchman (Atria, Mar.), about a hideous murder in 1793 Stockholm.

How did you decide to become a writer?

In my early teens, an illustrated comic duck—a Swedish satire of Donald Duck—inadvertently introduced me to the works of 18th-century poet and composer Carl Michael Bellman. Bellman chronicled the lives of the poor and the destitute in the Stockholm of his day, often with humor and tongue-in-cheek, but all of a sudden with a startling beauty that would make tears stream down my face. I learned then and there that an author is the finest thing you can be: a company for those who have none.

Had you always intended this book to be a mystery?

One of my big inspirations was Umberto Eco’s 1980 debut, The Name of the Rose. I read it as a thrilling mystery about murders in a medieval monastery. As I reread it years later, I was amazed to discover a layer beneath that, a convoluted history lesson about heresy and the controversial role of comedy and laughter in the doctrine of the Catholic church at the time. My unreserved love for that book made me foolish enough to attempt something similar: a layer of detective fiction to entertain those who look for entertainment, a layer of historical fact for those who enjoy such things, and a layer of Enlightenment thinking, of the conflict between reason and chaos, beneath that.

Why set it in 1793?

In early 1793, a new chief of police was elected in Stockholm, and one of the very few scraps of extant information about him is that he was an honest man. This also becomes his downfall; the administration wanted him to run their errands, not solve crime or make things better for the population of Stockholm. He gets sacked and sent into exile in December of 1793, the coldest winter in a long time. His tenure became the historical backdrop for my story.

Were there attorneys like your character Cecil Winge who aided the police in real life?

The phenomenon of the police in Sweden was only some 15 years old at the time and not very well chronicled. The common denominator of all parts of the Swedish state at this time is a sense of chaos. The lack of organization gave people in the right places a lot of leeway to do as they pleased, and if the police chief really was the honest man the sources tell us, I believe he could have grown frustrated at the inefficiency of his own agency and brought in able people as consultants. Nevertheless, with Cecil, I venture into the realm of what may not have been completely unlikely, and, happily for me, what at least will be very hard to disprove.