Game of Thrones may be blood-curdling and violent fare but its 65-year-old creator, George RR Martin, is a portly, softly spoken figure in black shirt and braces whose silver beard makes him look a little like Father Christmas as portrayed by Raymond Briggs. On a humid afternoon, he is sitting on a sofa in a suite at the Beau-Rivage, the most upmarket hotel in Neuchâtel, Switzerland.

The New Jersey-born writer is guest of honour at the Neuchâtel International Film Festival (NIFF), whose organisers are clearly delighted to have such an eminent figure in their midst. They confide that they have been startled by how amenable Martin has proved. "He wants to meet people," the festival's artistic director Anaïs Emery says with evident surprise as she details the many book signings, masterclasses and press events he has already attended. (He has also found time to visit the HR Giger Museum in nearby Gruyères.)

After my interview with him, Martin is due to introduce a screening of Alfred Hitchcock's Psycho that he has programmed (alongside two of his other favourite films, Casablanca and Forbidden Planet).

"I thought Psycho was an interesting choice because people are constantly saying I kill people in my work unexpectedly," says Martin, explaining his decision to unleash Hitchcock's mother-fixated maniac Norman Bates on the Swiss festival-goers.

Psycho is notorious for the scene of its ostensible star, Janet Leigh, being stabbed to death in the shower. This happens long before the final credits roll.

Game of Thrones has its own Psycho moments. For example, some fans still haven't quite forgiven Martin for killing off Ned Stark (played by Sean Bean in the HBO TV adaptation) so early in the story. After all, Ned was one of the heroes of the first series: a craggy, sable-covered patriarch, courageous and doggedly loyal, who was chief of the House of Stark. Martin, though, isn't about to apologise for taking off Ned's head.

"Hitchcock and [writer] Robert Bloch did that in Psycho. I wanted to establish that connection in particular. I am hardly the first person to kill a character unexpectedly and thereby get a big reaction from the audience."

Working primarily as a novelist, and now in television, Martin may seem an incongruous presence at a film festival but he is self-evidently a cinephile. In Santa Fe, where he has lived since the late 1970s, he owns and runs the Jean Cocteau Cinema. When he was growing up in Bayonne, New Jersey, cinema-going was as important to him as reading Marvel comics and Robert Heinlein sci-fi novels.

The picture Martin paints of himself as a kid growing up is Dickensian in its pathos. He was born in 1948. His family was very poor. His father was a longshoreman. Little George used to scrimp together money to buy comics and movie tickets by writing and performing "little monster stories". He sold them to the other kids in the projects for a nickel. (These were composed longhand, on school notebook paper.)

"When I was living in Bayonne, I desperately wanted to get away. Not because Bayonne was a bad place, mind you. Bayonne was a very nice place in some ways. But we were poor. We had no money. We never went anywhere."

His father, Raymond Collins Martin, spent around two years unemployed. Even when he eventually found employment as a longshoreman (and got his all-important union credentials), the work wasn't consistent. "You have a card and you have to show up at dawn every day," Martin says, recalling his father's working life. "Maybe you go home and you don't make anything. They hire the more seasoned men, the more veteran men. The longer you're in it, the more work you get but there are some rough times at the beginning."

The family didn't have a car. They lived on 1st Street. Martin walked every day to school on 5th street. The farthest he strayed from "the five blocks that seemed to be my lot," was when he took the bus to the cinema on 16th Street. Until he went to college (he studied journalism at Northwestern in Illinois), he lived a confined and claustrophobic existence. "There was a hunger in me to see more of the world, to see things I only read about in books."

Game of Thrones season 5 cast Show all 9 1 /9 Game of Thrones season 5 cast Game of Thrones season 5 cast Game of Thrones season 5 Oscar-nominated New Zealand actress Keisha Castle-Hughes will play the fiery Obara Sand, one of Prince Oberyn’s illegitimate daughters, who is seeking revenge for her father’s murder at the hands of the Mountain in season four Getty Images Game of Thrones season 5 cast Game of Thrones season 5 Nymeria “Nym” Sand will be played by Jessica Henwick, her best known role to date is in television series Silk and Spirit Warriors BBC Game of Thrones season 5 cast Game of Thrones season 5 Jonathan Pryce will star as the High Sparrow, a religious figure who could be making waves in King’s Landing Getty Images Game of Thrones season 5 cast Game of Thrones season 5 Alexander Siddig, who will be playing Doran Martell, the stoic ruler of Dorne and the older brother of the gruesomely slain Oberyn Getty Images Game of Thrones season 5 cast Game of Thrones season 5 Enzo Cilenti (left) will take on the part of the slave trader Yezzan Rex Features Game of Thrones season 5 cast Game of Thrones season 5 London-born star DeObia Oparei will play Areo Hotah, the loyal protector of Doran Martell Getty Images Game of Thrones season 5 cast Game of Thrones season 5 Rosabell Laurenti Sellers will play Tyene Sand, one of the illegitimate daughters of Oberyn Martell, the Prince of Dorne Getty Images Game of Thrones season 5 cast Game of Thrones season 5 Myrcella Baratheon will be played by newcomer Nell Tiger Free Rex Features Game of Thrones season 5 cast Game of Thrones season 5 Newcomer Toby Sebastian will take on the role of Trystane Martell, the youngest son of Doran

Thanks to his success, Martin can now of course travel far and wide. But even so, his nostalgia for his childhood is evident. He still goes back to Bayonne. "I miss the pizza, which is the best in the world, and I still have family there."

His father, who died before Martin made it big as a novelist, was not an expressive man. Nor did he care for literature (although he was proud his son made it to college.) "I don't think he ever read a book after he got out of school and he never finished high school."

Strangely, we have to thank the American world chess champion Bobby Fischer for Martin's emergence as a writer. Martin was a very proficient chess player himself.

"I started playing chess when I was quite young, in grade school. I played it through high school. In college, I founded the chess club. I was captain of the chess team."

In the American chess-rating system, Martin was categorised at his peak as "expert," one rank below "master".

"The importance of chess to me was not as a player but as a tournament director. In my early 20s, I was writing. I sold a few short stories. My big dream was to be a full-time writer and support myself with my fiction but I wasn't making enough money to pay my rent and pay the phone bill – so I had to have a day job."

In 1972, Bobby Fischer did Martin a huge favour by winning the world chess championship. "Bobby Fischer played Boris Spassky in Reykjavík and won – and the entire American chess community went nuts!"

On the back of Fischer's success, the game became hugely popular. Martin was hired to direct the Midwestern circuit for a national organisation that ran chess tournaments. "For two or three years, I had a pretty good situation. Most writers who have to have a day job work five days a week and then they have the weekend off to write. These chess tournaments were all on the weekend so I had to work on Saturday and Sunday – but then I had five days off to write. The chess generated enough money for me to pay my bills."

After a year or two, the American chess bubble burst. All those enthusiasts who had taken up the game after Fischer's victory over Spassky stopped playing. There was no longer much money in setting up tournaments. "But, by then, I was much better established as a writer," he reflects. "The chess really did mark a crucial turning point in my career."

Martin himself long ago gave up chess. He decided that he didn't have the dedication or love of the game to treat it as a full-time job. "You have to study the books and memorise the openings and play constantly, play games every day, over and over again," he sighs. "I wasn't willing to do that. I enjoyed chess, it was fun playing it and doing the tournaments but I didn't want to make it my job. Writing gave me much more satisfaction."

I ask Martin if all the tactical thinking and preparation involved in his chess career helped him later when he turned to constructing something as complex as A Song of Ice and Fire, the epic series of fantasy novels of which Game of Thrones was the first. Given the size of the enterprise, the vast cast of characters and huge array of subplots, how does he work out what fits where?

The author laughs ruefully. "I don't have an easy answer to that. I just do. It is in my mind. I have charts of course. Most of it is on the computer. I have files on the computer. I have lists of chronologies and family trees. I consult those from time to time but less than you would think. Most of it is just in my head."

Martin acknowledges that he is "aided" by the fact that he has written Ice and Fire in the age of the computer. Touchingly, he still types up his work on an ancient DOS word processor. "DOS with WordStar 4.0," he elaborates. "Primitive though it is, compared to certain systems, it has a search and replace function that is very useful. I have assembled all four of the published books into one gigantic document. If I am about to write about a character, Bill, I do a search and see every previous time I mentioned Bill and what I said about him. Even then, I still make mistakes because it is large. That is maybe one reason why I've slowed down a little, as I get deeper into it and it gets more and more complex, it is harder to remember. Maybe I take a little more time in reviewing what I did last week or last year or three years ago."

George RR Martin is greeted by fans before attending a book signing in Dijon, France (Getty Images)

The "slowing down" Martin mentions is a source of huge disquiet to some of his fans, who are desperate for him to finish his magnum opus as soon as possible. They take delays personally and have been at times vicious in their attacks on the author for keeping them waiting.

"I have the best fans in the world for the most part," Martin sighs. "There is a minority who are annoying, it has to be said. But for every one of those, there are 500 who are just great and who are very supportive. They buy the books and come out in their thousands when I do a signing."

The author seems grounded and phlegmatic but acknowledges the occasional bad review "sticks in the craw" and that he is still "bothered" by the sniping of some of his more aggressive fans, telling him to get a move on. "But I just have to accept it. It comes with the territory." As he tells himself, it's a problem most writers would "die to have."

"With most writers, no one gives a shit when their book is coming out and even when it does come out, no one cares. I would much rather have my problem than their problem."

Besides, before A Song of Ice and Fire started selling in the millions, Martin had his own share of "flops and failures" as he freely acknowledges. There were times when he thought his career was over.

The author has been a beneficiary of a digital age in which fans and authors have become closer than ever before. Nonetheless, he still believes in a traditional, ordered model of publishing in which manuscripts are crafted and refined – not simply dumped on the internet. He pays heartfelt tribute to his UK and US editors, Jane Johnson of HarperCollins and Anne Lesley Groell of Bantam Spectra. "They're both great. They read the books. They give me their commentary. I work with them on it. I think editors are still important."

Good editors, he continues, are "gatekeepers" who find and guide new talent. "The world is changing, I will admit. I am old enough and now very well established so the changes don't affect me so much. But with the rise of the internet and self-publishing, we are seeing people who are trying to reach the readers directly and bypass traditional publishing and bypass the editors. It is really too early to tell where that will lead but I am not necessarily sure it will lead to a good place. I do think the function of editors as gatekeepers is a valuable and worthy function – they do save us from reading a lot of crap!"

The novelist is midway through something of a European tour. After his trip to Switzerland, he is due in Scotland for the Edinburgh book festival. It has often been suggested that Ivanhoe (by the Scottish 19th-century novelist Walter Scott) was, alongside the War of the Roses, a major influence on A Song of Ice and Fire/Game of Thrones.

Martin was first turned on to Ivanhoe by the 1952 MGM movie starring Robert Taylor, George Sanders and a young Elizabeth Taylor. "I think it was Elizabeth Taylor at the peak of her...," his voice tails off before he clarifies. "She was the most beautiful woman in the world. I think I was nine years old when I saw that movie. How could you not fall in love with her? But the jousting and the pageantry of it made me love that story. Later, in high school, I did read that book. For a modern reader, it's a little tough to get through. The prose is very Victorian and thick but if you fight your way through it, the story is there. It has everything the movie has and more – the heraldry and jousting and the insight into the times. It was an influence in that sense."

Thanks to HBO's Game of Thrones, Martin is now a major figure in US TV as well as an author with the 21st-century's equivalent of the popularity and reach that Walter Scott once enjoyed. One of the producers of the TV series referred to it flippantly as: "The Sopranos in Middle Earth." Such a description isn't so far off the mark. Without The Sopranos, Martin acknowledges that Game of Thrones might never have been greenlit. In the 1980s, Martin had worked for CBS television on The Twilight Zone. The American television world he encountered then was very different from the one he thrives in today.

"Certainly, HBO and premium cable in general has none of the rigid censorship that you encountered on the traditional broadcast network," Martin muses. "The networks were looking for a very broad, general audience. They wanted all groups, all ages, all demographics, mass audiences – and they were definitely very afraid of offending anyone."

Huge fanbase: The author at a book signing in France (Rex Features)

This used to lead to bland, safety-first programme choices. "You had to write very sanitised stories," Martin remembers. "You always heard the phrase 'we're inviting people into our living room.' If there are obnoxious, mean people, we wouldn't invite them into the living room every week."

Martin credits David Chase's groundbreaking tale of a Mafia boss with changing this way of thinking. "The first episode of The Sopranos was one of the great changing points in television history. You meet this guy, Tony Soprano. You see him in this psychiatrist's office, talking about these ducks who have flown away. He seems like a very sympathetic guy. He's upset about ducks. You like him. Then, he's driving home. He sees this guy who owes him money and he runs him over with the car and gets out and starts kicking him. Maybe you don't like him so much but you are still ~ interested in him."

This was a lesson that Game of Thrones took to heart. Heroes don't have to be likeable. The Sopranos also proved that serialised dramas (as opposed to episodic dramas which could be shown in any order) could also work with audiences. Martin gives the example of Gunsmoke, a series that lasted for 20 years on American TV without seemingly changing. "Many people passed through Dodge City but at the end of the episode, Miss Kitty was in the Long Branch saloon, Doc was playing chess in his office and Matt Dillon and his deputy were down in the sheriff's office."

In Game of Thrones, by contrast, all is flux and chaos. This is TV drama on an epic, cinematic scale – one reason why Martin is so keen to round off the series with an actual movie.

"If we go seven or eight seasons and then the show is still big enough that we can get the $200m to finance a huge epic movie to end it… sure!" he enthuses about the prospect of a big-screen version.

In spite of the huge cast and very big budget ($6m per episode) of the television series, it is a source of frustration to the writer that not even HBO has the resources to do full justice to the original series of novels.

"We still run into budgetary problems. We've done a couple of great battles, for example, the Black Water battle in season two that I scripted and in this past season, episode nine was one long battle – the Battle of the Wall. Those have been great episodes, but we've also had to skip half the battles. Instead we have a messenger run on from off stage and say 'We've won the battle!' Battles are very expensive."

Martin would like any Game of Thrones movie to do full justice to the battles and to be shown on the biggest screen possible – but he does draw the line at 3D.

"I don't care about 3D," he says. "It gives me a headache."

In the meantime, Martin has work to do. He needs to complete writing his epic fantasy. When he finally does so, one prediction can safely be made. All those impatient readers who've been carping at him and telling him to get a move on are bound to feel a sense of loss. They will probably then regret that he didn't spend even longer spinning out his tale. That's the paradox – the fans are desperate to know the ending to a story that they want to go on forever.

George RR Martin will be speaking at the Edinburgh International Book Festival on Monday

OTHER NOTABLE AMATEUR CHESS PLAYERS

Stanley Kubrick

Used to play for money in Central Park. While filming '2001', he played 25 games with the scientist and writer Jeremy Bernstein.

Humphrey Bogart

Once drew against Grandmaster Samuel Reshevsky in 1956. One of his correspondence chess-game positions featured in 'Casablanca'.

Ray Charles