Herta Müller? The same Herta Müller who has no books in print in English? The German novelist whose sole presence in Waterstone’s is in a critical study entitled Body and Narrative in Contemporary Literatures in German?

So, Per Wästberg, chairman of the Nobel Prize Literature Committee, how do you explain the obscurity of this year’s winner? “She’s won every major prize in Germany. She’s very highly regarded across Europe.”

And how many British or American writers were on this year’s shortlist? “I can’t tell you that.” How about naming all last year’s nominees? “I can’t tell you that either. The list is secret for 50 years. After that, there is always a rush to see what the judges said about the great authors of their day. But I really can’t tell you now. ”

The world of the Nobel prize is sanctified and secretive. Most years the choice of winner baffles readers as much as it bemuses critics in America and Britain. Why has Philip Roth never won? How could Graham Greene be overlooked? What do Scandinavians know about literature anyway?

Wästberg, 75, a grave-looking gatekeeper in a charcoal shirt and jacket can answer these questions, but only when convention allows. One of the 18 members of the Swedish Academy and the public face of its five-strong literature group, he has been to prize-giving ceremonies since 1957, when Albert Camus won. As a journalist, he watched William Golding and John Steinbeck, addled by drink, claim their prizes. As an academician, he stood between Hermann Hesse and V. S. Naipaul as they came to blows in a radio discussion.

That last image is apt, if you buy into Wästberg’s way of seeing the globe. He believes Sweden has an excellent vantage point from which to referee the world of literature: on the margins, but part of the European tradition; linguistically separate from MTV and the rest, and fed by a more nourishing literary diet in translation.

“It is a great regret that the Anglo-Saxon world is so rich in itself but so insulated to the outer world,” says Wästberg, most of whose 50 or so novels and poetry books are unavailable in English (though an English translation of Wästberg’s latest novel will be published in the UK by Granta next spring). “Only detective stories cross borders. Nothing that is truly well-written and original counts. There are exceptions, but the poor British are often so astounded when it comes to a Nobel winner. They say, ‘Who is that? We haven’t heard of him.’ ”

This incredulity helps to build the mystique. Wästberg likes that. He loves the ceremony, too: December’s presentation in Stockholm Concert Hall; the “penguin mountain” of tuxedos that leads upwards to King Carl XVI Gustaf; the lecture by the award-winning laureate. Every year the winning author collects a prize of 10 million Swedish crowns (just over £1 million), and a publisher gloats over the marketing gain.

There have been mistakes. You’ll struggle to find early Nobel winners such as Theodor Mommsen or Bjørnstjerne Bjørnson in your local Waterstone’s, but you’ll have better luck with writers the academy overlooked: Henry James, Virginia Woolf, Edith Wharton, W. H. Auden and Greene, of course, all named with regret by Wästberg. “That is the sadness of it all,” he says. “The not winning of it.” But, he insists, after 1945, the Nobel prize came into its own. He reels off the “glorious list”: Hesse, Gide, Eliot, Faulkner . . .

It takes more than a year for the annual prize to come to fruition. In autumn, the Academy writes to 300 nominating authorities worldwide — national academies, university faculties, writers unions and past Nobel winners — and by February, a list of 220 contenders has been assembled. Researchers open files on the nominees, but the duffers are obvious — “some names are absolutely unknown to us and they remain unknown”, says Wästberg. Others have been long-listed because of blatant lobbying, by, say, universities in a particular country; they too are summarily dismissed.

The list contracts, first to 25, then to 15. By May, only five writers remain, and the Academy convenes to approve the literature committee’s shortlist, before retiring for a summer’s intensive reading: the entire works of each of the nominees. That’s a breeze for Wästberg, a “compulsive” reader, he says. “I don’t have any other hobbies. I don’t play golf. I don’t collect stamps.” When he travels, he carries his books in plain covers, just in case he’s spotted.

Unwritten rules help the academicians through the summer. In 1938, the American Pearl Buck (mawkish tales of downtrodden peasants) swept to the prize on a wave of popularity. Now deemed unworthy, her sudden elevation led to a convention that no one should win the prize the first time they are shortlisted. In practice, since some, if not all, the five writers have been nominated before, the Academy has already chewed over their stuff.

“One digests a writer over several years. We do not make spontaneous choices,” says Wästberg. That’s why the prize can sometimes seem like an afterthought. In January 2005, an ailing Harold Pinter announced he had laid down his pen; nine months later he was Nobel laureate. He said it felt like he’d risen from the dead.

But we’re getting ahead of ourselves, says Wästberg. When he and his four committee men have assessed the contenders, they each write essays on every one of the authors. In September, the 25 articles are distributed to the Academy, and a further three weeks’ debate ensues. At the end of the month, a first vote is taken, ratified seven days later — usually in the second week of October — by a secret ballot. At last, the winner is phoned.

That should be the end of the affair. But not always. In 2003, J. M. Coetzee, in Chicago, told the Swedes to ring back — it was 5am and he needed a shower before he entered the land of the living. In V. S. Naipaul’s case, the ring of the phone alerted only the author’s wife. She said: “Sir Vidiadhar always writes at this time of day. He is not to be disturbed.”

For Herta Müller the greatest prize came on Thursday, while she was minding her own business in her Berlin apartment. Now only Penguin Mountain remains to be conquered.

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