Last Sunday I made a pilgrimage to the Père Lachaise cemetery, in the northeast of Paris, to pay my respects to the shade of Oscar Wilde. I found I was not alone.

The great man’s grave was surrounded by quite a crowd, including a party of Japanese students, a family of Germans (the father was wearing lederhosen) and an assortment of young people in their twenties: French, Italian, British and American.

As I arrived, one of the young women (an English student from St Andrews) was planting a kiss on the huge Jacob Epstein effigy that surmounts the poet’s grave. She was kissing the marble deliberately, to leave the lipstick impression of her mouth on the monument. “Why did you do that?” I asked. “Because I love him,” she replied. “We all do,” added another of the girls. “He’s one of us.”

Wilde, it seems, is our contemporary. He died in Paris 108 years ago, a near-friendless exile, impoverished, shunned, disgraced. Today, he is world-famous and universally admired. There are 1,000 lipstick impressions on his tomb. He would not have quarrelled with the attention: he was a pioneer of celebrity culture. “If you wish for reputation and fame in the world,” he advised, “take every opportunity of advertising yourself. Remember the Latin saying, ‘Fame springs from one’s own house.’ ” At theatrical first nights, as a matter of policy, during the 10 minutes before the curtain was due to rise, he would make a series of brief appearances around the auditorium - in the dress circle, in the stalls, in the boxes on either side of the stage. He wore outlandish clothes; he said outrageous things. He set out to get himself noticed. He was.

And he is. I am writing a series of Victorian murder mysteries, traditional who-dunnits featuring Wilde as my detective, and, as my publishers cart me about the world, I am discovering that my hero’s fan base extends way beyond Europe and North America. He has a substantial following in South America, the Middle East, India and - wait for it - Korea. Other Victorian writers may be more widely read (Dickens and Conan Doyle, for example), but I reckon that no other individual Victorian, however eminent (no, not Queen Victoria herself), lives on as a personality in quite the way that Wilde does.

How come? In his day, Wilde - iconoclastic, bisexual, Irish - found fame and, briefly, fortune by dint of genius, charm and application. In his own time, he was an outsider and an exotic. Now he’s one of us. We understand his craving for celebrity. We share his obsession with youth. (“Youth is the one thing worth having,” he wrote in The Picture of Dorian Gray.) Gay or straight, we are easy with his sexuality. Indeed, so prejudiced are we in his favour, we tend to overlook the fact that most of the young men in whom he took an interest were little more than boys.

At the time of his arrest and imprisonment for homosexual offences in 1895, all but a handful of his contemporaries abandoned him. To us, his downfall adds to his allure. Ours is the age of the misery memoir. The greater your trauma - the more disturbing your childhood - the faster you climb the bestseller list. In 2008, Oscar would have made a packet. Alongside the public humiliation, he knew private heartache. He had a philandering father, a drunken brother and a favourite younger sister, Isola, who died when she was 10. He carried a lock of her hair for the rest of his life. (He also had two half-sisters who burnt to death in a domestic fire.) At a familial level, the real tragedy of his life was that, from the moment of his disgrace, he was prevented from seeing either of his young sons. (Wilde had many faults, but he was a devoted father.)

When he was released from Reading Gaol in May 1897, Wilde fled straight to France. Now, of course, as well as being showered with potential publishing deals, he would have been rushed towards the television studios - and he wouldn’t have blown it. He was no Heather Mills, our Oscar. He was the master (almost the inventor) of the telling soundbite. (“In olden days men had the rack; now they have the press.”) He’d have given Jeremy Paxman a run for his money. He’d have had Jonathan Ross gagging with delight.

Wilde disconcerted his contemporaries because he challenged the certainties of his age. We no longer have any certainties so we find that, in his behaviour, his dress, his aphorisms, he speaks to us directly. In a rigidly hierarchical world, in an age when an Englishman’s world-view was entirely Anglocentric, Wilde, an intellectual Irishman, ignored the barriers of class (he was easy with everyone, princes and prostitutes) and thought of himself as a citizen of the world. He spoke several languages; he travelled extensively.

In London, Wilde lived among the myth-makers. He was an acquaintance of Robert Louis Stevenson, who created Dr Jekyll and Mr Hyde. He was a friend of Bram Stoker. (Dracula was published on the day Wilde was released from prison.) In Dorian Gray, with the portrait in the attic, Wilde created one myth, but in himself, consciously, he also created another, even more potent.

As a character to play with in a novel, I love him. He is fabulous and at the same time real; heroic yet flawed. As a Victorian detective, he is ideal because he dared to live (and think) outside the box and he was a friend of Conan Doyle and an admirer of another mythic figure, Sherlock Holmes. As a phenomenon, I am in his debt because it turns out that - like Shakespeare and Coca-Cola - he is a brand, with brand values we respond to.

And, as with all the best brands, his name says it all. He rather thought it might. “I began life,” he said, “as Oscar Fingal O’Flahertie Wills Wilde - a name with two Os, two Fs and two Ws . . . But a name which is destined to be in everybody’s mouth must not be too long. It comes so expensive in the advertisements! When one is unknown, a number of names is useful, perhaps needful, but as one becomes famous one sheds some of them, just as a balloonist, when riding higher, sheds unnecessary ballast . . . All but two of my five names have already been thrown overboard. In time, I shall discard another. A century from now, my friends will call me Oscar; my enemies will call me Wilde.”

Oscar Wilde and the Ring of Death by Gyles Brandreth will be published by John Murray on May 1

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