IN Arnaldur Indridason’s crime novels the Icelandic gloom is more than a meteorological condition. For two decades now Indridason has been publishing spare, haunted novels full of pain and grief and bad weather.

His Detective Erlendur series is set in a contemporary Iceland that has all the problems you’d expect of a modern nation (Erlendur himself has a failed marriage and a daughter who, in some of the novels, is a heroin addict), but they are also steeped in the island’s history and mythology.

His taciturn, solitary, dogged hero spends his nights brooding on his cases or the Icelandic sagas. If anything, Indridason’s new book, The Shadow District, sees him move deeper into the gloom. The first of a trilogy, it has a dual timeframe, as a murder case from wartime Reykjavik echoes through the years to the present day.

Here, Indridason talks about the morality of crime fiction, why the past is always present and why football is making him miserable these days.

The Shadow District marks a new start and a new series for you. What prompted you to launch a new series and what did you want to explore?

Well, the new books are a trilogy taking place in Reykjavik during the Second World War. I have been interested in the period for quite some time and written to some extent about it in books like Silence of the Grave. This time I wanted to look into it a bit more, with these three books taking place between the years 1940 and 1944, from the British occupation to Iceland becoming independent from Denmark. It is a very important period in the history of Iceland, the time when our isolation in the North Atlantic was fully broken and we became part of global events and a quite important part at that. Since then nothing has been the same for us.

Was it an era you knew much about?

No. I had read a little about it and heard stories from people who lived it and I got interested in the sheer social aspect of 40,000 troops coming to Reykjavik which had about 40,000 inhabitants. Soon we had one of the biggest naval stations in the Atlantic at a place called Hvalfjördur, about an hour from Reykjavik. The sheer size of it within such a small community as Iceland is mind-boggling. And there were all kinds of problems we had to deal with, not the least the attraction between the soldiers and the women in Iceland and I write a bit about that in my books.

Iceland was a very poor peasant society at the time with a growing fishery industry, but then everybody that could do so moved to Reykjavík and into the villages and we never looked back. There was work to be had everywhere, women got more freedom and more opportunities in life and in the aftermath of the war Iceland became a very rich modern society. That ended, of course, in the big crash of 2008 – as we all know. Probably this all happened too fast.

It's a novel that plays out against a background of older stories about the huldufolk (the mythological hidden people or elves). What do Icelanders really feel about those old stories now? Has that changed in the last 50 years as the country has modernised?

Oh, absolutely, we don’t believe in elves and trolls and ghosts as we used to. Probably the electricity changed all that. There was a time when we collected all these stories and published them and they were very popular. Now it is all part of old folklore, although we still move big rocks with great care if they stand in the way of new roads and we suspect there are elves living in them. I have no idea why that is still going on.

I use these stories in The Shadow District as a kind of connection with the old times when people had to be at peace with the elves or the “huldufolk”, the hidden people, out in the countryside or most terrible things would happen.

We think of crime fiction as a genre concerned with contemporary issues but the past is always present in your fiction. Why so?

The past is fascinating to me. It has something to do with the concept of time itself. My books are very much a form of time travel, going back in time to the past and then forward again to our era and trying to find out what happened in between. How time has changed us or not changed us. How time stops somehow and we can’t get it back on track as in the case of my policeman, Erlendur, in the Erlendur series. Something happens to him at a very young age and he can’t cope with it and somehow time stands still after that and he can’t connect to his times anymore and becomes this loner who lives in the past.

And it’s about memories and how you cling to them and how they affect your life. So my books are absolutely not about how to live in “the now,” but how to cope with the past.

In fact your books always remind me of that William Faulkner line: "The past is never dead. It's not even past." Would you agree?

For me Faulkner got it right. The past is always there if you want it or if you don’t want it or need to learn from it and is such a huge part of us that it never really passes but clings on forever. For others it doesn’t exist at all and they could not care less about what happened in the past. I think they must be the happy people we sometimes hear about.

Is this an age thing? As we get older the past begins to consume us more than the future.

It has always been like that for me and it is probably the reason why I learned History at the University of Iceland.

For you is crime fiction a moral form?

I like to see myself as a moral writer without the preaching aspects of it. I don’t like to preach to people and tell them what to think or what is right and what is wrong. They have to find out for themselves. But I like to put forward the moral questions and the doubts and the ambiguity in our existence and the crime novels are an excellent venue for that. They go to the extreme of the human experience and are able to tackle the moral issues of our times in a very simple and clear-cut way.

Iceland has changed dramatically since the wartime setting of The Shadow District. Do you think it is a different country now?

Very much so. Just as the world is different. We were far more isolated then. Now we are very much a part of the globalisation everybody is talking about and not everybody likes so much. And we are drowning in tourists. Iceland seems to be in fashion nowadays and it’s a whole new invasion we are experiencing now, with more than two million tourists coming to Iceland every year. That’s something for a population of 330,000.

Iceland is a country with a small population. And the crime rate is proportionate. So why do you think so many Icelandic writers turn to crime fiction? (Or is that a British perception?)

We have more crime writers now than ever. It has not so much to do with crime rate which is low in Iceland, although we have all the usual crimes like drugs and violence and prostitution and even human trafficking. The murder rate is very low.

In my mind crime fiction is not about crime rate but people, and places and storytelling; ordinary people getting into extreme situations, about the sorrow and the missing and feelings of anger and hate and love and all these emotions we go through in our lives. To have a location like Iceland is just icing on the cake.

How do you think you have changed as a writer since you started?

I am always trying to be a better writer and have a better understanding of the craft of writing and storytelling within the genre of crime novels. I haven’t changed my methods much as I try always to be organised and go to work every day and write, even if it is only a few sentences.

I am also looking more into the characterisation in my books and the people that inhabit them because I think that if you don’t have any interest in the characters of the novels you read, there is little point in telling the story.

When you are not writing, what is the shape of life?

I try to watch my Arsenal games at the weekends – and it is more difficult now than ever.

The Shadow District, by Arnaldur Indridason is published by Harvill Secker, £12.99