Her father, the son of Scottish lawyer and cricketer David Dundas Whigham, was chairman of the Celanese Corporation of Britain and North America.

Her beauty was much spoken of, and she had youthful romances with Prince Aly Khan, millionaire aviator Glen Kidston and publishing heir Max Aitken, later the second Lord Beaverbrook.

[1] However, the wedding did not take place because she preferred Charles Francis Sweeny (1910-1993), an American businessman and amateur golfer from a wealthy Pennsylvania family.

[6] For the rest of her life, Margaret was associated with glamour and elegance, being a firm client of Hartnell, Victor Stiebel, and Angele Delanghe in London before and after the Second World War.

She also had a serious romantic relationship with Theodore Rousseau, curator of the Metropolitan Museum of Art, who was, she recalled, "highly intelligent, witty and self-confident to the point of arrogance".

As a young woman I had been constantly photographed, written about, flattered, admired, included in the Ten Best-Dressed Women in the World list, and mentioned by Cole Porter in the words of his hit song "You're the Top".

The Duke was known to be addicted to alcohol, gambling and prescription drugs, and was described as physically violent and emotionally abusive by his first two wives, whose money he tried to use to maintain Inveraray Castle.

[12] He suspected the Duchess of infidelity and, while she was in New York, engaged a locksmith to break open a cupboard at their Mayfair home, 48 Upper Grosvenor Street.

The evidence discovered resulted in the 1963 divorce case,[13] in which the Duke accused his wife of infidelity and included a set of Polaroid photographs of the Duchess naked, save for her signature three-strand pearl necklace, in the company of another man.

It was speculated that this "headless man" was the Minister of Defence Duncan Sandys (later Lord Duncan-Sandys, former son-in-law of Winston Churchill), who offered to resign from the cabinet.

[15] She dropped her case the day of the hearing due to lack of a witness, and later had to pay a judgment of £25,000 to her stepmother, who sued her for libel, slander, and conspiracy to suborn perjury.

Lord Denning, who was called upon by the government to track down the "headless man", compared the handwriting of the five leading "suspects", (Duncan Sandys; Douglas Fairbanks, Jr.; John Cohane, an American businessman; Peter Combe, a former press officer at the Savoy Hotel; and Sigismund von Braun, brother of the German scientist Wernher von Braun) with the captions written on the photographs.

[10] Granting the divorce, Lord Wheatley, the presiding judge, said the evidence established that the Duchess "was a completely promiscuous woman whose sexual appetite could only be satisfied with a number of men".

Long afterwards, it was claimed that there were actually two "headless men" in the photographs, Fairbanks and Sandys, the latter identified on the basis of the Duchess's statement that "the only Polaroid camera in the country at that time had been lent to the Ministry of Defence".

[14] In 2013, the daughter-in-law of the 11th Duke, Lady Colin Campbell, stated that the "headless man" was an American executive named Bill Lyons.

With her fortune diminished, she opened her London house at 48 Upper Grosvenor Street, which had been decorated for her parents in 1935 by Syrie Maugham,[19] for paid tours.