A secular kind of sainthood has been conferred upon Diana, Princess of Wales. What does it tell us, asks Paul Vallely, about a society where religious observance has withered and yet the instinct for it survives
If Jesus Christ were killed in the modern age it would be in a car crash, or so JG Ballard said in the novel on which the notorious film, Crash, is based. It is a wilful post-modern confusion. Ever since the death of James Dean the fatal crash has had an iconic status. It speaks of youth and untimely death. Some of that has invariably attached itself to the death of Diana, Princess of Wales. She is illuminated too by the precedent of Marilyn Monroe, a beauty cut off before her time. But perhaps the most interesting of the templates laid upon her is to be found in the spontaneous secular canonisation which a nation largely without religion has conferred upon her.

The process has a precedent. A kind of secular sainthood has been bestowed upon Elvis Presley. At the recent celebrations to mark the 20th anniversary of his death there were vigils, candles, tears and even Hallelujahs at Graceland. Elvis is a source of comfort in times of trouble to many and to some he is even a resurrected figure. Certain kinds of death prompt thoughts of sainthood, most particularly tremendous and ignominious suffering. After which, death demotes and then erases all traces of human frailty. With saints people forget the bad points.

The words "saint" and "martyr" have been common among the sea of flowers at the royal gates. The ritual of leaving wrapped-up flowers at the scene of a violent death has become commonplace over the past decade. It speaks of a need for ritual among even those with no religion and it creates a new sense of shrine.

Saints and shrines accumulate power and presence. Pilgrims travel, often in groups, to places where sacred power is found, to acquire something of it and take it back with them into their everyday lives. It is not something much approved of in Protestant theology which prefers to concentrate sacrality on people rather than places. That is why shrines and pilgrimage have not been British phenomenon since the Reformation.

But such dogma has evaporated along with the religion which spawned it, and the public have returned to pagan instincts which other religions never abandoned. Roman Catholics have always been keen (they have 6,000 shrines in western Europe, 65 per cent of them dedicated to the Virgin Mary). Buddhists make pilgrimages not to power, but to light. Even Zionism might be seen as a collective pilgrimage.

The more arduous the pilgrimage, of course, the greater the benefit derived. Which is why 750,000 people queued for more than eight hours to sign books of condolence for Diana. It was the queuing that was important; that and being there with others, for pilgrimage is most often a shared experience. Pilgrims usually need to leave something behind. Some take things away, which explains the tacky religious souvenir shops in places like Lourdes. But most want to leave something. The instinct which prompts people to throw money into pools (and which prompts the non gettare moneta alla tomba sign at the tomb of the Italian mystic Padre Pio) also inspires them to lay flowers, and with them, epithets or rhymes.

At the Western Wall in Jerusalem the faithful cram prayers on scraps of paper into the cracks between the stones. At St Ninian's cave in Whithorn they do the same, or leave stones from the beach marked with crosses. In St James's Palace they leave messages in condolences books so numerous that they will never be read. No matter. There is an act of healing in writing.

The full gamut of religious experience is reflected in this secular sainthood. As well as the quiet devotion, we have already had an apparition of Diana appearing on a portrait of Charles I in St James's Palace and an appearance by Diana, through the mouth of a psychic, live on radio in North Carolina.

Is all this in any way a valid expression of religious feeling or is it a mere corruption? Sadly there is something kitsch about it because the myth is kitsch, even as it was with Evita. Eating disorders are only a pale reflection of holy fasting, just as the Marilyn Monroe archetype is only a vulgarised version of Ophelia, Cordelia or every other woman wronged. It is a complex business. Myths are there for re-creating. It was Mother Teresa who described Diana as an ordinary housewife who was in love with the poor. And Diana fed the myth herself; when asked by Le Monde for her favourite photograph, she chose a non-glamour shot of herself holding a child with cancer in Pakistan.

Of course a high percentage of female saints were queens: the imperial Helena, Margaret of Scotland, Elizabeth of Hungary, Isabella of Portugal. And it didn't end after the Middle Ages. Sixty-two years after the death of Queen Astrid of the Belgians - in a car crash at the age of 30 - devotees continue to visit the chapel built on the spot of the accident by Lake Lucerne. At one point 120,000 people a year came to pay their respects.

Such an influx is what was feared by Rev David MacPherson, vicar of the 13th-century church of St Mary the Virgin, in Great Brington, which is the resting place for 20 generations of the Spencer family. A new shrine would have been created in a tiny place which would struggle to cope with the influx of "pilgrims". A populace starved of other outlets for its religious instincts would have flocked there. Perhaps that is one reason why Diana will be laid to rest in the grounds of Althorp, where it will easier to control visitors.