Sex, psychoanalysis, intimate operations and a winning way with flashers - how eye-popping Marie Bonaparte put even her maverick nephew, Prince Philip, in the shade...

The Duke of Edinburgh was a larger-than-life character, but even he paled to next to his colourful aunt, Marie.

A relative of Napoleon Bonaparte she was a fascinating character, famed for her all-consuming interest in sex and psychoanalysis, her friendship with Sigmund Freud and her unconventional lifestyle.

She also had a highly effective way of dealing with flashers... 

Born Marie Bonaparte in 1882, Marie was the great-granddaughter of Napoleon I's rebellious younger brother Lucien. 

Princess Marie Bonaparte, Napoleon's niece was Prince Philip's aunt. She led a colourful and independent life 

Lucien Bonaparte younger brother of Napoleon was father of Princess Marie Bonaparte

Prince George of Greece with his wife, Marie Bonaparte. George appears to have had little interest in the opposite sex

A portrait of Prince Philip, son of Prince Andrew of Greece and Princess Alice of Battenburg taken in 1927. Philip would then have been aged five or six

She was fabulously rich thanks to her maternal grandfather François Blanc who made his fortune on real-estate development in Monaco, buying 97 percent of the casino in Monte Carlo.

Her wealth made it possible for her to bankroll Prince Philip's family after they were forced to flee from Greece at the end of the Greco-Turkish War in 1922. 

(It was Marie who paid for Philip to be educated at The Elms, an American school in Paris. Paradoxically she sent her own children, Prince Peter and Princess Eugénie to the local state-run lycée feeling it was important they should mix with children of all backgrounds.)

In 1907, Marie married Philip's paternal uncle Prince George of Greece. 

George has a footnote in history for saving the future Tsar Nicholas II of Russia from assassination during a visit to Otsu, Japan in 1891. 

The Tsarevich was attacked by a policeman with a sword who turned out to be a former Samurai with a grudge against westerners. George managed to knock him to the ground using his cane.

George appeared to have little interest in the opposite sex. Indeed, he was  passionately in love with his own uncle, Prince Valdemar of Denmark, the youngest brother of Britain's Queen Alexandra (wife of Edward VII)

It was unsurprising, then that George and Marie's marriage was relatively passionless. 

The groom never allowed his new wife to kiss him on the lips and after the honeymoon she wrote: 'You took me that night in a short brutal gesture, as if forcing yourself. You said “I hate it as much as you do. But we must do it if we want children“.'

Marie would seek love elsewhere and,  accruing a long list of willing sexual partners, Marie documented them in her unpublished 1918 memoirs 'The Men I Have Loved.'

Marie enjoyed an equally fulfilling life out of bed. 

She was a close friend of Sigmund Freud who mentored her interest in psychoanalysis and who once memorably asked her 'what does a women want?' - presumably feeling if anyone would know it would be the princess. 

She carried out her own study on frigidity under the pseudonym A. E. Narjani. 

Her theory was that the closer the clitoris was to the vagina the more chance a woman had of achieving an orgasm. 

To back this up, she personally measured this crucial distance in 243 women. 

Satisfied she had discovered the truth, she had her own clitoris surgically shifted a few inches in what she believed to be the right direction. Unfortunately both this and a subsequent operation failed in its ultimate goal.

So focused was she on the benefits of psychoanalysis that when she was once flashed at on the Rue de Boulogne' she handed the baffled perpetrator her card and the offer of a free session on her analyst's couch a gesture that sent him scuttling away.

Marie also had an interest in the criminal mind, describing Jack the Ripper as 'a super-murderer and a super-anarchist.'

 In 1934 she published The Life and Works of Edgar Allan Poe: A Psycho-Analytic Interpretation with a foreword by Sigmund Freud.

The princess's writings also give a vivid picture of some of Prince Philip's relatives. 

She described his mother, Princess Alice, as 'a beautiful blond, Englishwoman with ample flesh, smiles a lot and doesn't say much as she's deaf.' 

 She has also left us a fascinating vignette of Queen Alexandra whom she found '63 years old [in 1907], surprisingly young, enamelled skin. Disturbing when youthfulness covers an old skin. She seems kind and friendly, but also insignificance personified.'

Prince George and Marie maintained strong links with the British royal family particularly after Prince Philip joined what George VI referred to as 'the firm.' 

They represented the King of Greece at the 1911 Coronation of George V and half a century later stood in for King Paul at the 1953 Coronation of Queen Elizabeth II. 

They were also present in Westminster Abbey to witness the marriage of their niece Princess Marina of Greece to Prince George, Duke of Kent in 1934 and again 13 years later for Philip's marriage to Princess Elizabeth.

Prince Andrew of Greece, fourth son of King George I of Greece (and a nephew of Queen Alexandra) together with his fiancee, Prince Alice of Battenberg. Andrew and Alice were the parents of Prince Philip

Princess Marie Bonaparte and her children Pierre and Eugenie of Greece

Marie Bonaparte with husband Prince George of Greece And Denmark. They are photographed at the Paris opera in 1954

Philip stayed in touch with Marie for the rest of her life and she was present with George when the Greek royal family were reunited at Tatoi, the summer palace near Athens, for a private visit of Elizabeth and Philip in December 1950. 

The Queen and Prince Philip enjoyed several dinners with George and Marie, both private and formal.

Marie wrote to one friend: 'Grand dinner at court for Elizabeth and Philip, decorations, tiaras, horror!'

The most unconventional of princesses, remained a maverick to the end.