Prince Charles only married Princess Diana because his father sent him a threatening letter telling him to propose because her ‘reputation was on the line’.
Charles panicked when he got the note from Prince Philip amid fears in the royal family that his indecision had ‘impugned' her honor.
He thought that Philip, who communicated with his son by letter and not by speaking to him, was issuing him an order that said: ‘You’ve got to get engaged’.
According to family friend Pamela Hicks, Charles ‘wasn’t in love, he wasn’t ready….psychologically he assumed his father bullied him, so he read it as a bullying letter’.
The extraordinary claim is in a new biography of Charles by New York Times bestselling author and royal family biographer Sally Bedell Smith.
She chronicles the life of the heir to the throne in a riveting ,Prince Charles: The Passions and Paradoxes of an Improbable Life, which will be released on April 4.
She details how Charles and Diana were a terrible match from the start of their ill-fated union in July 1981.
Charles only married Diana, a former kindergarten teacher, because his real love Camilla Shand, now his second wife, Camilla, Duchess of Cornwall, was not virginal enough for royal custom.
During their rows at Kensington Palace Diana used to taunt Charles that he would ‘never be king’, knowing it caused him deep consternation.
Bedell Smith claims that Diana used to hit Charles over the head when he knelt down to pray by their bed at night - and continue berating him during his prayers.
The book portrays Charles, 68, in an unflattering light and writes that he and his staff ‘dealt with Diana’s bewildering and often infuriating behavior by placating her, trying to distract her and, ultimately, out of frustration, abandoning her’.
The book makes it clear that the real love of Charles’ life is Camilla, 69, whom he first met in 1972.
Camilla was an upper class girl and he daughter of a British Army officer with a low, husky voice.
Lady Annabel Goldsmith called her ‘an intensely warm maternal laughing creature, with enormous sex appeal’.
Charles adored how Camilla ‘always listened’ to him, Bedell Smith writes, and in her he ‘found the warmth that he yearned for’.
But it wasn’t to be because Charles was not ready to settle down with her at the age of 24.
More importantly family friend Patricia Mountbatten said there were ‘obvious problems’ with Camilla.
The conventions of the time called for a princess to be virginal, or at least appear so, and Camilla ‘had a history’, as Mountbatten put it, ‘and you didn’t want a past that hung about’.
Even though Camilla married another man, Andrew Parker Bowles, her affair with Charles would continue for much of his marriage to Diana.
By the time Charles reached the age of 30, the pressure to get married was intense and after a series of flings Diana entered his life.