Top historical novelist Robert Harris talks to Hannah Stephenson about how his life has changed since his blockbuster debut novel, and why he doesn't feel the pressure he once did.

When bestselling novelist Robert Harris found himself in a German apartment where Hitler, Mussolini, French premier Edouard Daladier and British Prime Minister Neville Chamberlain signed the Munich agreement in 1938, in an effort to keep peace prior to World War II, he felt the hairs stand up on the back of his neck.

"Hitler's apartment, which isn't open to the public, remains remarkably unchanged," he observes. "It's part of a police headquarters. The balcony where Hitler used to stand and show himself to the crowds is still there - I stood on it. I sat in the same spot in which he and Chamberlain talked."

The days leading up to the Munich Agreement - in which Britain, France and Italy gave the Sudetenland (an area of Czechoslovakia bordering Germany) to Hitler for appeasement - without asking Czechoslovakia - form the backdrop to his latest story.

So when describing the apartment in his twelfth novel Munich, he was able to bring the scene to life with vivid descriptions of real artefacts of history, a subject which has been his obsession for years.

The setting may be real, but the plot centres on two fictional protagonists, former Oxford University friends - the first now one of Chamberlain's private secretaries, and the other, a German diplomat and secret member of the anti-Hitler resistance.

Their paths cross again as they try to persuade Chamberlain not to sign the agreement and to stop the Fuhrer from starting a war.

"I made a BBC Two documentary nearly 30 years ago - before I'd even become a novelist, which marked the 50th anniversary of Munich. I'm fascinated by the way people still talk about Munich and appeasement today, and the moral dilemmas."

Harris, 60, was a political journalist who worked on BBC programmes including Panorama and Newsnight, and became political editor of The Observer before the mammoth success of his debut novel Fatherland enabled him to become a full-time novelist.

Fatherland - the alternative history tale set in a world where Nazi Germany had won the Second World War - became an immediate bestseller and has since sold more than three million copies translated into 25 languages.

"It completely turned my life upside down. It was entirely unexpected. I had no idea it would have the effect it had. It changed everything in a great way, although it left me feeling a little disorientated to begin with, because I wasn't sure what it was about Fatherland that people liked so much."

The success put huge pressure on him to deliver an equally captivating second novel, he recalls.

"I knew a lot of people would be looking at it to see if I could do it again, and I took three years to write the next book. I had a year or more when I couldn't really work. It's the only time I've had bad writer's block.

"For a long time, books took me a long time to write and then I started to speed up as I got older. I became less frightened of writing, stopped worrying about it so much and probably knew what I was doing more."

In subsequent years, Harris has turned his hand to code-breaking (Enigma), modern Russia (Archangel), ancient Rome (Pompeii, Lustrum), Tony Blair (The Ghost), the Dreyfus affair (An Officer And A Spy) and a very 21st-century financial meltdown (The Fear Index).

Does he miss the cut and thrust of politics now?

"I still follow it closely. I don't miss being on a newspaper. I much prefer writing fiction than being a lobby correspondent. One of the benefits of the modern world is that we're all in politics now. You can see it in real time. Almost everything is laid bare to us."

A one-time close friend of Tony Blair - whom he later described as a 'narcissist with a messiah complex' - Harris says he rejoined the Labour Party last year.

"We seem to live in an age of highly unlikely things happening in politics," he muses. "Who would have thought Brexit or Trump? It's a revolutionary time. There's almost nothing you could tell me will happen next year that would surprise me."

'Spin' may have become the buzzword of the Blair years, but Harris says image is as present now as it always has been.

"Image has been important in politics since the Roman times, and probably before that. It's as much the way you say it as what you say, how you look and the sense of authority - those are vital things.

"If you look at Theresa May, part of the problem is that she looks so uneasy and unrelaxed. Whenever I see her doing anything public, she looks like she wishes she was somewhere else. It's not a good look, but the theatre of politics has always fascinated me. It's the great soap opera of our time."

Today, he lives in an enormous pile in the Berkshire countryside with his wife Gill Hornby, also a writer and the sister of author Nick Hornby. They have four children.

"We talk about books and share the opening of a book to one another. But in the end, writing is a solitary activity and you just have to do it on your own," notes Harris.

Some of his books - Fatherland, The Ghost Writer, Enigma - have been adapted for screen and some have been better than others, he reflects.

"It takes the books to a different audience and it's interesting to see the stories coming round again in a different form," he says diplomatically.

"I enjoyed The Ghost, probably because I wrote the screenplay. I wasn't very thrilled with Fatherland, where they changed a lot of the plot and weakened the story, but there's no point in complaining about it.

"My brother-in-law [Nick Hornby] put it rather well. He said it's like selling your house and then coming back the following year and complaining because they've knocked through the kitchen. If you don't want it changed, don't sell it."

Still, there are several adaptations of his work in production, including a TV series of The Fear Index and the Cicero novels, and Conclave is set to be a feature film.

"I don't know whether they'll happen, but they are all in the hands of good people."

  • Munich by Robert Harris is published by Hutchinson, priced £20. Available now.