The writer Neal Stephenson, in response to a question about his own fame or lack of it, came up with a usefully precise and clarifying answer:

It helps to put this in perspective by likening me to the mayor of Des Moines, Iowa. It’s true of both the mayor of Des Moines and of me that, out of the world’s population of some six billion people, there are a few hundred thousand who consider us important, and who recognise us by name. In the case of the mayor of Des Moines, that is simply the population of the Des Moines metropolitan area. In my case, it is the approximate number of people who are avid readers of my books. In addition, there might be as many as a million or two who would find my name vaguely familiar if they saw it; the same is probably true of the mayor of Des Moines.

The crucial contributing factor to this condition, which involves being both incredibly, outlandishly famous by serious-writer standards while also being unknown to the general reader, is the fact that Stephenson works in the area of SF and fantasy writing. For reasons I’ve never seen explained or even thoroughly engaged with, there seems to be an unbridgeable crevasse between the SF/fantasy audience and the wider literate public. People who don’t usually read, say, thrillers or military history or popular science will read, say, Gone Girl or Berlin or Bad Pharma. But people who don’t read fantasy just simply, permanently, 100 per cent don’t read fantasy.

That doesn’t stop some of these books finding many millions of readers. The works that do so, though, are almost always crossovers from the category of teen, or as the industry calls it, ‘young adult’, fiction. Harry Potter, the Hunger Games, and the Twilight novels are all in this category, and they’re also not individual works but series. When they found a wider readership they didn’t do so in a merely big way but in an apocalyptically huge one. Given permission to read books of this kind – permission derived from the books’ success – people have shown that they are willing to wolf them down by the millions. (It’s a subject in its own right, the self-reinforcing phenomenon of the contemporary mega-seller; by which I mean not just the garden variety bestseller but the book or books which go to that mysterious other place in the popular consciousness, when it’s as if reading them has somehow been made compulsory.) This surely implies that there is nothing innate to fantasy which puts people off reading it. But there does appear to be something off-putting about fantasy as an idea. The fact that people are willing to read fantasy novels in practice emphasises the parallel fact that, most of the time, they aren’t willing to read them in principle. They’re only willing to read the freak mega-sellers: fantasy itself is off limits to large sections of the general reading public.

Auden thought that admiration for Tolkien was an indispensable sign of good literary judgment. That’s putting it too strongly, but you could certainly say that a willingness to read Tolkien with an open mind, and pass judgment on the work’s merits or lack of them, is a sign that no preconceptions about literary categories are in place. I once had to speak up for The Lord of the Rings at a retrospective version of the Booker Prize for 1954 – the other candidates were Under the Net, The New Men, Lucky Jim, A Proper Marriage and Lord of the Flies, which won – and needless to say I was the first to be chucked out of the metaphorical balloon. It was clear, though, that not only had a large part of the audience not read the book, there were no circumstances under which they would consider doing so. There was something depressing about that.

When you ask people why they don’t read fantasy, they usually say something along the lines of, ‘because elves don’t exist’. This makes no sense as an objection. Huge swathes of imaginative literature concern things that don’t exist, and as it happens, things that don’t exist feature particularly prominently in the English literary tradition. We’re very good at things that don’t exist. The fantastic is central not just to the English canon – Spenser, Shakespeare, even Dickens – but also to our amazing parallel tradition of para-literary works, from Carroll to Conan Doyle to Stoker to Tolkien, Lewis, Rowling, Pullman. There’s no other body of literature quite like it: just consider the comparative absence of fantasy from the French and Russian traditions. And yet it’s perfectly normal for widely literate general readers to admit that they read no fantasy at all. I know, because I often ask. It’s as if there is some mysterious fantasy-reading switch that in many people is set to ‘off’. And it’s this that leads to the mayor of Des Moines syndrome, because part of the point of Stephenson’s remark isn’t just that people who don’t live there don’t know who the mayor is, they couldn’t care less. The information is of no use to them.

Until recently, George R.R. Martin would’ve been another serious candidate for that mayoralty. He has for decades been an immensely prolific and successful writer of fantasy, unusual in having more than one series on the go simultaneously. (He’s also a fan of his own milieu. Martin held the first numbered ticket to the first Comicon festival, the now famous, gigantic orgy of all things fantastic and SF and geeky. It is impossible to have a more profound qualification as a fan of his own genre: it’s as if Comic Book Guy from The Simpsons turned out to be George Lucas.) Martin is now much more widely famous thanks to his novel cycle A Song of Ice and Fire, perhaps better known, thanks to the immense success of the HBO series, as Game of Thrones, which took its title from the first novel in the series. Game of Thrones was first described to me, by someone familiar with the project from before its initial broadcast, as ‘The Sopranos meets Lord of the Rings.’ At that point, I knew I was going to like it. But then, I am that person – the one who likes fantasy and SF. It was far from clear that anyone else would like it. So I have to admit I feel an obscure and entirely unjustified sense of vindication at the fact that now, with the third series about to start airing, Game of Thrones is universally seen as a roaring success, and Martin’s books have hit the best-seller lists, many years after they were first published. (The first book in the sequence came out in 1996.)

There are five novels in the series so far; at the moment the projected length of the full cycle is seven books, but the work has already stretched from its initial design of five books to seven, so further stretching feels possible. Martin has said that his ambition was to create an imaginary world with the atmosphere of the Wars of the Roses. A small number of aristocratic families are contending for power on the kingdom of Westeros, an island with a cold north, warm south, varied topology, and ferocious barbarians across the seas to the east. The families are interlinked by marriages and alliances, but remain strongly distinct in ethos. The Starks are the heroes, the family at the heart of the story: they are northerners, hard people adapted to a hard life, preoccupied by honour. Their patriarch, Eddard Stark, is a gem of a part for Sean Bean in the TV series. The Lannisters are their enemies and opposites: rich, ruthless, amoral southerners, barely able to conceal their wish to take over the kingship. As for the king, at the start of the books that is Robert Baratheon, the huge bruiser who, with help from the Starks, deposed the previous king 17 years before the story begins. That monarch, mad King Aerys, was the last Targaryen on the throne; the Targaryen dynasty rode to power in Westeros hundreds of years ago on the backs of dragons, practised brother-sister incest, and gradually went mad. But the dragons are long dead – none has been seen for hundreds of years – and the two last Targaryens, the only family members to survive Robert’s attempt to eradicate them all, are near-children, fled into exile over the seas. Another of the families, the Tyrells, become increasingly central to the books from the third novel onwards: they are courtly, mannerly and utterly unscrupulous – ‘Lannisters with flowers’.

The books tell this story by hopping about from person to person across the wide geography of Westeros and beyond, with the point of view moving around a large rep company of principal characters, most of them, most of the time, afraid for their lives. The Wars of the Roses, in this reimagining, are – as they surely were in real life – a blood-soaked, treacherous, unstable world, saturated in political rivalries, in which nobody is safe. The violence in this milieu is not Tolkienian sword-fighting between warriors and orcs: it is long on murder of the innocent, poisoning and rape. It’s not a world any sane person would want to live in, not for a moment; which is another respect in which it manages to resemble the real Middle Ages.

This sense of unsafety and instability is at the heart of the books. I’ve been acting as a kind of low level pusher or drug dealer for the series, shoving recommendations and occasionally box sets in the direction of friends. I tell them to forge past their elves-don’t-exist resistance at least until the end of the first episode. And that, generally, is all it takes. After that initial act of drug-pushing, I follow up on my new clients to ask how they have got on with the series. Everyone is addicted, and everyone reports the same moment as being the one that got them hooked. (From this point onwards, this piece doesn’t so much contain spoilers: it is in itself one big spoiler. Be warned; or, better still, don’t be warned: stop reading now and give Game of Thrones a go for yourself.) It’s right at the end of the first episode. Robert Baratheon has gone north to visit his old friend Eddard Stark, to ask him to come south to the capital, King’s Landing, and become ‘the Hand of the King’, in charge of the practical running of the kingdom. (As the saying has it, ‘the king eats and the hand takes the shit.’) With Robert is his wife, Cersei, a Lannister, gorgeous and ruthless, and her twin brother, Jaime, universally known as ‘the Kingslayer’ because he was the one who murdered the mad king. He did so in defiance of his oath as a member of the Kingsguard, an order of knights sworn to defend the king’s life; Jaime is universally regarded as a very bad man, treacherous and amoral. These two Lannister twins are blond and beautiful; their third sibling, Tyrion, also part of the king’s travelling party, is a dwarf, a worldly, jaded, funny, highly intelligent cynic and, as incarnated by Peter Dinklage, the indisputable star turn of the HBO series.

The king and his entourage take up residence at Winterfell, ancestral home of the Starks. We see much of their antics from the perspective of Bran Stark, second-youngest son of Eddard, a likeable, lively eight-year-old boy. Bran’s hobby is climbing all over the huge high rambling castle of Winterfell, something he does with an enthusiasm which would be reckless if it weren’t for his complete confidence that he will never fall. In the course of one of his climbs, he hears adult voices through a high window, goes to investigate, and comes across Jaime and Cersei energetically engaged in (to use a neologism popular with fans) twincest. They catch him catching them at it, and Jaime grabs Bran. The two twins look at each other. ‘The things I do for love,’ says Jaime – and throws the boy out the window.

That startling moment is where the first programme in the TV series ends, and it’s the point at which people realise they’re addicted. It has an equivalent impact in the books; even more of an impact, perhaps, because Bran has already been established as one of the characters from whose viewpoint the story is told. Plus, he’s only eight. This is a world in which nobody is safe, ever. The image of a fall from a high place is relevant: in this world, everyone’s position is precarious. ‘This is the game of thrones,’ Cersei tells Eddard Stark, ‘you win or you die.’ That exchange is crucial to the whole multi-book arc of the story. It was initiated by Eddard, who has gone to warn Cersei that she is at risk. Eddard has worked out, first, that the previous Hand of the King was murdered; second, that he was murdered at Cersei’s instigation; third, that he was murdered because he had worked out that the king’s two children are not, as it happens, his children at all. Instead they are the offspring of Cersei and Jaime’s twincest (see how useful that word turns out to be?).

Eddard knows how insanely angry Robert is likely to be, and although he dislikes and distrusts Cersei, he tells her his discovery, as he says, ‘out of mercy’. When overthrowing the previous dynasty, Robert killed every Targaryen he could find, including children and babies. Eddard thinks he will do the same to Cersei and her children, hence the warning: he wants Cersei to take them and flee for her life. What she does instead is arrange for Robert’s death, stage a coup to put her son on the throne, and have Eddard executed for treason – the scene which ends the first series of the TV show. Eddard’s sense of honour and mercy has catastrophic consequences. The movement towards his death is so painful, so inexorable, that the reader/viewer feels sure something, anything, must be coming along to avert it. Most consumers of popular culture have been trained to expect happy endings, last-minute reprieves, a lucky break for the good guy in a tight spot. In Game of Thrones, the good guy has his head forced down on the block and then chopped off, in the presence of two of his daughters.

Westeros is by now in a full state of civil war. This is where the second book and second TV series, A Clash of Kings, begins. There are now no fewer than three declared kings in Westeros. Representing the Baratheons is the handsome, charismatic, impetuous younger brother Renly. (HBO further develops their normal policy on gratuitous sex scenes – that policy being that they’re strongly in favour – by giving him a gratuitous gay sex scene.) He dies. The Lannisters are led by the patriarch Tywin, who is calculating, brutal and ruthless even by Lannister standards. He dies. The Starks are led by Eddard’s eldest son, Robb, a mere teenager (though he’s older on the telly): he is brave, so charismatic that his followers anoint him the ‘King in the North’, a brilliant war leader. He dies. The nominal king is Joffrey, officially Robert’s son but in reality Cersei and Jaime’s – people don’t know that, but there are beginning to be rumours. Joffrey starts out by seeming nothing more than a nasty little shit, but before long turns out to be genuinely psychotic. He dies. These are not peripheral figures but richly imagined, textured, three-dimensional portraits of central characters: the kind many writers couldn’t bear to kill off. Nobody needs to give Martin any advice about how he needs to slaughter his darlings.

The sense of instability goes beyond not knowing who’s going to survive and who’s going to be the next apparently principal character to be killed. Our judgments of people in the story are also unstable. One of the most compelling aspects of this next series of Game of Thrones is what happens to Jaime Lannister, who is firmly lodged in the reader’s imagination as utterly irredeemable – amoral, ruthless, violent. (Though one issue about this new series is just how much of the novel sequence it will contain. The book which was published in the USA as one gigantic volume, A Storm of Swords, was two books in the UK. A lot happens in each of them and the rumour at the moment, just pre-airing, is that the new series will concentrate on roughly the first half of the big book.) At one point, while he’s held captive by the Starks during the war, Catelyn Stark is taunting him and uses the expression, ‘men like you’. Jaime’s response is immediate: ‘There are no men like me.’ We believe him.

We still believe him in this new series, but we also come to learn that Jaime is a much more complicated character than he initially seemed, with a code of behaviour not much less rigid than Eddard Stark’s: his act of ‘kingslaying’ saved many innocent lives, and his twincest with Cersei is a lifelong act of devotion – she’s the only woman he’s ever slept with. He has his sword arm chopped off, too, so this damaged, loyal/treacherous, honorable/conscienceless figure becomes increasingly complicated and, in his uncategorisable way, even heroic. The idea of character ‘arcs’ in popular fiction and movies has been so strip-mined, become so jaded and familiar, that it’s refreshing and almost alarming to have a story carry the reader so far away from her initial perceptions of a character. What this all boils down to is that in the world of these stories, you are given something that is extremely rare in a mass-market form: you genuinely don’t know what’s going to happen next.

That, I think, is the first reason for the immense popularity and success of Game of Thrones. This sense of instability, of not knowing what’s about to happen, speaks to the moment. We all feel anxious and uncertain about the future, none of us knows quite how firmly our feet are planted. It’s hard to dramatise economic uncertainty, so why not convey this feeling through a made-up version of the Wars of the Roses? Add the depth and texture and profoundly satisfying thoroughness with which Martin has imagined this world, and the range of his imaginative sympathy with its large company of characters, and it’s a wonder it’s taken the world so long to fall in love with the books.

The second big reason for the success of the series may be adjacent to the point about instability. It concerns magic. The whole issue of magic, in turn, seems to be the principal turn-off (‘elves don’t exist’) for non-readers of fantasy. In Westeros, people agree with that. They don’t believe in magic either. There used to be dragons, not just in the distant mythological past but in historical memory, and the dragons’ skulls are preserved as relics. But the dragons got smaller over time, and then died out, and with them the magic left the world. In the north of Westeros there’s a 700-foot-high wall, built to keep out ‘white walkers’, terrifying undead magical sort-of zombies who once lived in this same north and were a mortal danger to men. The wall is guarded by the Night’s Watch, a sworn order of men who take a lifelong oath to defend the world to the south from the white walkers. But nobody apart from them still believes in the white walkers. As Tyrion puts it, the Watch are there to defend Westeros from ‘grumkins and snarks and all the other monsters your wet nurse warned you about’. The Night’s Watch has become a dumping ground for the kingdom’s losers and criminals, and their membership consists of (Tyrion again) ‘sullen peasants, debtors, poachers, rapers, thieves and bastards’.

The reader, however, knows different. The very first scene in the huge saga begins with three members of the Night’s Watch, on a mission north of the wall, coming into contact with white walkers and meeting a horrible end as a result. The Night’s Watch, and the ‘wildings’, outlaws who live north of the wall, are the only people in the world who believe in the white walkers – but we readers know they are a real and imminent danger. We know also that dragons have been reborn into the world, thanks to Daenerys Targaryen, who fled Robert Baratheon’s infanticidal wrath as a mere baby and has grown up over the seas and to the east of Westeros, where she was married off by her brother to Khal Drogo, the terrifyingly martial Dothraki ‘horse lord’ – the Dothraki being a bit like the Mongols. (Oh, in case you’re wondering – he dies.) In the coup de théâtre that ends the first series, Daenerys climbs into a funeral pyre carrying three dragon eggs, and emerges at dawn with three baby dragons, the first the world has seen in hundreds of years. We surmise, from these events and from the title of the sequence, that Westeros is heading for a white walker v. dragon stand-off, at some exciting juncture a couple of fat novels away.

So the reader knows that magic is real, but the people of Westeros think that it isn’t; with one big exception, and it is this exception that is, I think, the second structural reason for this story’s appeal right here, right now. This is to do with the seasons. In Westeros, seasons last not for months but for years, and are not predictable in duration. Nobody knows when – to borrow the minatory motto of the Starks – ‘winter is coming.’ At the start of Game of Thrones, summer has been going on for years, and the younger generation has no memory of anything else; the blithe young aristocrats who’ve grown up in this environment are, in Catelyn’s mordant judgment, ‘the knights of summer’. The first signs of autumn are at hand, however, and the maesters – they’re the caste of priest/doctor/scientists – have made an official announcement that winter is indeed on its way. A winter that is always notoriously hard, and can last not just years but a decade or more. It’s a huge all-encompassing environmental force, determining the lives of everyone, open-endedly. The climate change aspect of this is obvious to the contemporary audience, but there’s something more subtle and subtextual at work here too: another economic metaphor, another kind of difficult climate. Westeros is like our own world, in which hard times have arrived, and no one feels immune from their consequences, and no one knows how long the freeze will last. Our freeze is economic, but still. Put these two components together, and even the fantasy-averse, surely, can start to see the contemporary appeal of this story, this world. It’s a universe in which nobody is secure, and the climate is getting steadily harder, and no one knows when the good weather will return.

There’s one more point to be made concerning instability and unpredictability. That is the issue of how long it’s going to take Martin to finish the books. After getting hooked via the first TV series, and before starting out on the books, I did something I hardly ever do, and looked up Martin’s Amazon reviews, to see how far he was into the series and how long he had to go. The world of Amazon comments on Martin is, even by the standards of Amazon-comment-world, peculiar. (My single favourite fact about Amazon-comment-world: Newt Gingrich’s Amazon reviews, which I unironically recommend for anyone interested in his core field of geopolitical history, says he is ‘the’ Newt Gingrich, with inverted commas around the ‘the’.) Everyone loves Martin’s books, which have hundreds of maximally favourable ratings, but that’s not what you’re likely to encounter first when you look him up. Instead you’re greeted by dozens of posts with headings such as ‘Do not buy any product by George R.R. Martin’ or ‘Do not read this book’ or ‘Warning! Avoid!’ This fan ire has its basis in the fact that Martin hasn’t got closer to finishing the series. That’s a trifle harsh, one might think, given that he has written several thousand pages so far – but the fans’ point is that the rate has been slowing down. A Game of Thrones came out in August 1996, A Clash of Kings 27 months later, A Storm of Swords 21 months after that, but then the gap between the books grew: A Feast for Crows took five years and then A Dance with Dragons six years more. Half a decade is a long time between books in a work that is conceived and published as a series. At the current rate, even if the sequence doesn’t expand any further, he won’t be finished until 2020. It’s also the case that the narrative momentum of the series has slowed in books four and five, and the exploration of Westeros feels more leisurely and expansive, with the books’ stories in many cases overlapping and simultaneous.

The fans don’t like that, partly because – this is bad taste and I apologise, but there’s no way round it – they’re worried that Martin is going to die before he finishes. The whole letting-the-fans-down-by-dying issue is a sore point in the world of fantasy, thanks to the death of one of the most admired contemporary writers of fantasy, Robert Jordan, before he had completed his own multi-book cycle, The Wheel of Time. That cycle is being finished by Brandon Sanderson, whose work is admired, but we can all agree that however fine the execution it’s not quite the same thing. The fans’ concern is that Martin just isn’t getting on with it. Martin is very active at going to conferences and on book tours and has other creative projects on the go, as well as an active website selling T-shirts, figurines and tat, and he blogs too, and many of his readers want him to stop doing all that and just get his head down to finish the books. That’s harsh, very harsh … and yet the fan part of me wants him to get on with it too. So this is the final anxiety about the world of Westeros. Part of the piquancy is that we readers don’t want to get to the end of it, and yet we want it to be finished, so we can get to the end of the story when we so choose. Our sneaking fear is that Martin, too, may not want to come to the end of it, a wish for which we couldn’t blame him. Except blame him is exactly what we would do, if he doesn’t come to the end. Winter isn’t just coming, it’s already here, and one of the things we all like to do in winter is feel sure that somewhere out there, even if we can’t yet see it or sense it, there’s an ending.