Diana, Princess of Wales, bewitched Britain but not her prince, and the consequent rupture of their loveless marriage cast a shadow over the long-term future of the British monarchy. Not since the abdication of King Edward VIII in 1936 had the royal family's private life so seriously imperilled its future.
The "fairytale" partnership of the Prince and Princess of Wales ended in a public relations fiasco of "his and hers" biographies and television interviews which made divorce inevitable as the only means of salvaging the dignity of the monarchy.
"It has all the ingredients of a Greek tragedy," Prince Charles lamented. "I never thought it would end up like this. How could I have got it all so wrong?"
Revelations of their extramarital affairs made even sympathisers question the judgment and moral authority of the heir to the throne.
When the princess cast doubt publicly on her husband's fitness to become king, Queen Elizabeth responded by pressing her son and daughter-in-law to end the marriage.
Diana was undoubtedly one of the world's most popular and photographed women, and the loyalty of her admiring public survived the descent from princely wedding to drawn-out drama of domestic strife.
There was something of My Fair Lady about the shy bride moulded by her "Professor Higgins", a husband 13 years her senior, until she learned her royal role and went her own way. The prince had never seen his part as that of a superstar, while his wife undoubtedly did.
The marriage was never quite any of the things it seemed. It was neither purely an arranged marriage, nor a romantic fairytale, nor the modern union between prince and commoner that was supposed to breathe new life into the monarchy.
Prince Charles never loved his wife, according to Jonathan Dimbleby's authorised biography, and proposed to her only because his father had bullied him into it.
A gold bracelet from Charles to his mistress, Mrs Camilla Parker-Bowles, that the princess discovered among the presents a few days before their wedding became the fulcrum of anger and jealousy that rent the marriage.
On their honeymoon on the royal yacht Britannia, her husband kept in touch with his Mrs Parker-Bowles.
His wife never forgave him, and rejection was at the root of her implacable enmity. As a child, she felt rejected. As a young wife, she was spurned.
Like many warring couples who bring out the worst in their partners, they nearly destroyed each other.
The seeds of this very contemporary tragedy were sown in their respective childhoods.
Her father, the eighth Earl Spencer, had been an equerry to both George VI and Queen Elizabeth. Her maternal grandmother, Ruth, Lady Fermoy, was a close friend and lady-in-waiting to the Queen Mother.
The Honourable Diana Spencer was born on July 1st, 1961, at Park House, Sandringham, close to the great Norfolk house which had been a retreat of the royal family since the days of Edward VII.
The third daughter of Viscount Althorp, then aged 37, and Viscountess Althorp, 12 years his junior, was quite literally the girl next door. Her childhood playmates were Prince Andrew and Prince Edward.
But she was only six when her mother left her father for the wallpaper heir Peter Shand Kydd. The viscountess sought custody of her two youngest children, Diana and Charles Althorp, but was thwarted by her mother, Ruth, who told the court that they should remain with their father.
The couple were divorced in 1969 and Lady Diana continued to live at Park House until the death of her grandfather, the seventh earl, in 1975 when the family moved to the Spencer family seat at Althorp House in Northamptonshire.
Diana went to Riddlesworth Hall, a boarding school near Diss in Norfolk when she was nine. Even at the best of times, school was not an institution in which Diana would shine, at least not academically. With the inevitability of family tradition, she went on to West Heath, the all-girls public school near Sevenoaks, where her mother had gone. She failed her O levels, even at the second taking and left school at 16.
After a brief stay at the Institut Alpin Videmanette, an expensive Swiss finishing school, her father bought her a flat that she shared with friends near Kensington. Three days a week, she worked for well-heeled friends, cleaning floors for £1 an hour, serving canapes at cocktail parties and acting as nanny. Then she became an assistant at the Young England kindergarten in Pimlico.
Her sister, Jane, had married Robert Fellowes, then an assistant private secretary to the queen, and this brought Diana increased contact with the royal family and the Prince of Wales.
Their closely guarded romance became public knowledge soon after a journalist turned his binoculars on them one late summer day in 1980.
The engagement was announced in February 1981. When asked if they were in love, Diana replied "Of course," but the prince added inauspiciously: "Whatever love is."
Their wedding at Westminster Abbey on July 29th, 1981 was a fairytale occasion on which it seemed the hopes of the UK - and the future of the monarchy - depended.
From the start, it was clear that the 12 year age gap was going to be a problem. His older, wiser friends intimidated and bored her. Her younger, brighter set irritated him. She did not care for his polo, or for the country pursuits which were the centre of his family's life. He was not at home in discos, or even on the dance floor, and preferred Berlioz to Dire Straits.
Much was made of her careful "grooming" for royal life. Yet in reality, she found the transition to her royal role a great strain.
Soon she was wandering the palace corridors wearing a gold-plated Walkman, shutting out the royal world in which she felt ever less at home. She told friends she felt bewildered and lost. The royal couple undertook an intensive programme of official home and overseas visits.
At first overwhelmed by the crowds who turned out to see her, the shy teenager quickly became a young woman of violent mood swings, according to Jonathan Dimbleby. Often the princess was in tears as she and the prince travelled to venues, pleading that she could not cope.
Feeling trapped and frightened in a gilded cage, the "Prisoner of Wales" began to suffer from bulimia nervosa, commonly known as slimmer's disease. Unable to deal with growing depression, she sought help by attempting suicide on more than one occasion.
Andrew Morton, her unofficial biographer, said Diana slashed at her wrists with a razor blade, a penknife and a lemon slicer and once threw herself against a glass cabinet.
After the birth of Prince William five months later, Prince Charles was asked about married life: "It's all right, but it interferes with my hunting."
The princess's progress from popular idol to saint, achieved through her remarkable personal warmth as comforter of the sick, the dying and the needy, was not easy for her husband to swallow. She won worldwide acclaim for her espousal of the cause of AIDS victims. But within the royal family, she seems to have been regarded as an uncontrollable "wild card" and to have been isolated accordingly.
No single event can be said to have caused the breakdown of the marriage. Charles told television viewers that he was faithful to Diana until the relationship had "irretrievably broken down" - in the second half of the 1980s.
The princess said it was effectively over after the birth of her second son, Prince Harry, in September 1984.
Rage and rows were reported as commonplace. The prince stuck rigidly to his annual schedule of polo, hunting, shooting and fishing, regardless of school holidays or family weekends. Diana sank into the trough of bulimia.
A holiday in the summer of 1986 first publicly exposed the cracks in the marriage. He came home three days early from Majorca, leaving behind his wife and sons, then aged four and two. It was said that the prince was going fishing. Many later believed that the real reason was that he wanted to join Mrs Parker-Bowles in Scotland.
Newspapers asked, "Are Charles and Di still in tune?" Buckingham Palace insisted everything was fine.
Her husband's early departure set a pattern that was to become familiar over the next six years. They spoke little and appeared to go out of their way to avoid each other's company. In February 1987, the couple visited Portugal together but hotel staff said they had separate bedrooms. By the autumn, they were leading separate lives, sometimes not meeting for up to a month.
The princess sought friendship outside her marriage - with used-car dealer James Gilbey and Major James Hewitt, a handsome Life Guards officer. Throughout 1988, Diana was treated by an eminent London psychiatrist, Dr Maurice Lipsedge. He broke her dependency on the gorging and rejection of food, which is the foundation of bulimia.
By 1991 the marriage was teetering on the edge, with former royal policeman Andrew Jacques revealing: "They never smile, laugh or do anything together. They seem to want as little contact as possible."
Buckingham Palace sought to dismiss such reports as "complete rubbish" until Viscount Rothermere, proprietor of the Daily Mail, told Lord McGregor, then chairman of the Press Complaints Commission, that Charles and Diana had recruited national newspapers to carry their sides of the story.
Then came Andrew Morton's bombshell book Diana: Her True Story, written with her tacit consent. It portrayed a lonely, neurotic princess, driven to tears, bulimia and tantrums by her unhappy marriage. It exposed the prince as a distant father, uncaring husband and adulterer. Diana continued to maintain her hold on public sympathy and affection despite the publication of tapes of intimate telephone conversations, known as the "Squidgy Affair", apparently between her and James Gilbey, whose voice could be heard professing love. A taped conversation between the prince and Mrs Parker-Bowles was also published.
A disastrous tour of Korea by the couple in November 1992 was followed a month later by Buckingham Palace's announcement of the separation.
In December 1993 the princess announced she intended to reduce her official engagements and develop a more private life. But just four months later she took on the role of Red Cross roving ambassador.
In June, 1994 the prince admitted that he had been unfaithful in a television interview with Jonathan Dimbleby. In his biography, published four months later, he said he had never loved his wife and married her only because his father had bullied him into it.
In August, 1994 Diana was linked with England rugby captain Will Carling and, two months later, Anna Pasternak's book Princess in Love chronicled her five-year affair with Major Hewitt.
She questioned her estranged husband's suitability to become king in a sensational television interview in November 1995, suggesting that she would prefer the succession to go to Prince William.
She declared that she had no intention of initiating a divorce, but the interview had a contrary effect. Her remarks about the succession, in particular, directly challenged Buckingham Palace and launched republican elements of the Labour Party into a discussion of the need for debate on the future of the monarchy.
Four weeks after Diana's appearance on Panorama, the queen wrote to her son and daughter-in-law urging a quick divorce in order to spare the feelings of the children.
In February 1996, three years after the separation, the princess brokered the final terms of a deal with her husband in his apartment at St James's Palace. Afterwards, she telephoned the queen and ordered an announcement that she had agreed to a divorce.
Buckingham Palace, taken by surprise, reacted with anger and disputed her claim to have resolved the contentious issues of her title, home, office and access to her two sons.
Diana was associated with about 150 charities in all, and was patron or president of 69 charities in the UK and 12 overseas.