What elevated Diana from the simply glamorous to the iconographic, however, was not just her many faces: it was her endlessly enigmatic personality. There have been other modern legends, of course–Marilyn Monroe, Princess Grace, Jacqueline Onassis. But no other woman so captured the Zeitgeist of this particular age than Diana. She began as ““Dynasty Di’’ in the go-go ’80s but ultimately became a very ’90s kind of figure–a serious-minded single mother struggling to recover from a broken marriage. Hers was not an easy journey: she was, at different times, sex symbol, virgin mother, grieving wife, avenging saint and, finally, liberated woman.

I would not have thought that she would have come so far, so quickly, when she walked into a meet-the-press party in the unlikely setting of a casino hotel in Alice Springs, Australia, in 1983. It was the first day of her first overseas visit of her blossoming royal career, and it was my first proper examination of the woman who would touch all our lives. She was jet-lagged, red-faced from sunbathing–and very nervous about meeting the media.

Way back then she was happy to play the role of dutiful child bride, anxiously following in the footsteps of her articulate husband. In those far-off days, royal men were judged by what they said and royal women by what they wore. Diana was more than happy to conform. In her first TV interview she admitted: ““I feel my role is supporting my husband whenever I can, and always being behind him, encouraging him. And also, most important, being a mother and a wife. And that’s what I try to achieve.’’ Feminists groaned, but those inside the palace redoubt were quietly satisfied. This marriage was conforming exactly to script.

Then the royal couple started to forget their lines. In the mid-1980s, Diana, wife and mother, turned into a fashion queen while her husband devolved into a figure of fun, a man who talked to plants when he wasn’t delivering woolly, indecipherable speeches. Meanwhile, there were even deeper tensions developing in the royal fairy tale. The princess had been clinically depressed after the birth of Prince William; she suffered from the eating disorder bulimia nervosa, and was perennially jealous of her husband’s relationship with Camilla Parker Bowles. By the early 1990s, the princess had entered what she was to call the ““dark ages’’ of her royal career. She felt powerless and frustrated. In any earlier era, she would have had no way out of her unhappy marriage–and no way to alter her image of superficial glamour. She would have been a latter-day Queen Alexandra, the betrayed wife of Edward VII: celebrated for beauty, refinement and grace but trapped with an unfaithful husband.

But the times, and Diana, were different. As her private life disintegrated, she gained strength–and public support, a useful weapon in her war against the Windsors–from comforting the sick. She was surprised to find that when she embraced emotions and causes which others, particularly the royal family, shied away from, it gave her the will to carry on.

Confined as much by her image as her royal position, her marriage effectively over, Diana’s tacit cooperation for my book, ““Diana: Her True Story,’’ broke the cycle of defeat and sacrifice. For the first time it told the unvarnished truth about the hostile palace establishment and her distant husband. Her ensuing transformation from silent victim to eloquent ambassador was probably the defining moment of her life. She was finally able to shape her own agenda and style. It was an achievement not lost on ordinary people, especially women. I received many, many letters, mainly from American women, who sensed in Diana echoes of their own lives and their own struggles.

““I see myself as a princess for the world, not the Princess of Wales,’’ she once said. Her sentiments may have been grandiose, but they were not arrogant. In the three years or so before her death she was learning her true power to move people and to draw them into the causes she espoused. Her decision to auction her gowns in New York for AIDS charities symbolized a de- liberate shedding of the past: the royal clotheshorse had become a workhorse. Perhaps the crowning achievement of her career was her campaign against land mines, a concern that symbolized how Diana’s appeal now had a truly global resonance.

As she stood on the brink of a new life, her past, a universe she could never escape, caught up with her in the shape of the trailing paparazzi. She may have flown the cage of Buckingham Palace and liberated herself as a woman in her own right, but the world would never let her break out from her abiding image as a glamorous and rather frivolous woman. Her life came a tragic full circle: the camera loved her to death.