It was a frigid 9 degrees in Boston on Monday, a brutal temp for walking the dog, but a great one for curling up with some classic Scandinavian crime fiction.

"Jar City." "The Snowman." "The Return of The Dancing Master." Just about everything by Stieg Larsson. You could argue crime fiction is one of the region’s biggest cultural exports.

And for some reason, the villains in the books are often Nazis, neo-Nazis, or people with Nazism in their past.

UC Berkeley's Linda Rugg says that isn't a coincidence.

"Sweden, during the Second World War, was neutral. Norway and Denmark were occupied, along with Finland, by the Nazis," she says. "So they all have a past relationship with Nazism.”

Rugg says you see the theme in books by authors like Henning Mankel, where one character sold black-market meat to the Nazis. She also cites the example of Jo Nesbo, who wrote a Norwegian character who served with the German army. “So they are sort of excavating a past that they had buried for a long time,” she says. “And that feeds into today’s neo-Nazi movement, which draws heavily on the past.”

One past skeleton in Sweden’s closet was a eugenics program. It covered the sorts of topics the Nazis examined, like the particularly dark study of “racial hygiene.”

So where do the novelists fit into all this? They certainly mine the history. But Rugg says for some there is more to it. “Henning Mankel was first published by a radical press,” she says. “And he really thought of himself as being a political messenger.”

Add Jo Nesbo and the late Stieg Larsson to that group of Scandinavian writers with a mission.

But does the message really make a political impact?

Rugg isn’t all that certain. She says it’s more that the crime fiction reflects some of the concerns Scandinavian societies have.

And that's influenced perceptions form the outside, perhaps more than events inside Scandinavia.

"The fiction has gained international recognition and has spread not only throughout the English speaking world but also been translated into many other languages. So what’s happened is that the image that we have of Scandinavia from the outside is produced by a large degree by the crime fiction,” Rugg says. “It’s not a total picture of Scandinavia. And I don’t think Scandinavians would see themselves as influenced by the crime fiction.”