The Sphinx — the woman who dreamt of becoming a duchess

Back in his teens, Hugo Vickers read a diary snippet about Gladys Deacon, “the love of Proust, the belle amie of Anatole France”, and how the world’s most beautiful woman had become, by 1943, a “terrifying apparition” who fled when accosted in a Bond Street jeweller’s shop by a former friend. She was never seen again.

Vickers was spellbound. The Sphinx, narrated with an admirable balance of sympathy and wit, unveils the bizarre life and eventually ruined features of an American heiress who dreamt of being a duchess. It concludes with the extraordinary story of how a persevering young biographer tracked down the nonagenarian Gladys (Glay-dis, should you wish to sound authoritative) in an asylum and became — after being subjected to hum­iliations that would have most of us running for the exit — her last true friend.

Colourful seems too quiet a word for the life of Gladys Deacon. Born in 1881, she was 11 when her father was jailed for shooting his wife’s lover in a hotel bedroom in Cannes (Henry James toyed with this new “donnée”, but dropped it).

A fortune teller informed young Gladys that she would become the Duchess of Marlborough, and mistress of the palace of Blenheim, the trophy house presented to John Churchill, the first duke, in gratitude for his victory over the French in 1704. The 14-year-old took it hard, then, when the duke married Consuelo, a Vanderbilt heiress. Besieged by a multitude of suitors, with whom she could converse in seven languages while dazzling them with her intellect (“I was a miracle! Differential calculus was too low for me!”), Gladys declined the lot, her azure eyes levelled like gun beads at the still unavailable duke.

A cache of marvellously spiky letters from Bernard Berenson’s wife to her Quaker mother (the perpetually randy art collector was hot on Gladys’s tail within a year of his own marriage) reminds us that Miss Deacon was not without her flaws. She is “like Sphinx, like Medusa”, Mary Berenson gasped, adding that Gladys’s capacity for telling lies was downright breathtaking.

Mendacity didn’t deter admirers, who included the Kaiser’s eldest son, Gertrude Stein’s brother and — after his own fashion — Proust. (“I never saw a girl with so much beauty, so much magnificent intelligence, such goodness and charm.”) In 1919 Proust, robed in a sealskin dressing gown, was among the imp­robable guests (Edith Wharton, Cole Porter, Marshal Foch) who celebrated Gladys’s triumphant bagging of her prey.

Becoming a duchess had taken quite a while. Gladys was nearing 40 and the wax she had injected to obtain a more Grecian profile had already melted, detracting from her former beauty. Not that the couple seemed too bothered, even when a flustered cleric asked Marlborough to take “this man” to be his wedded wife.

Poor Gladys. Brutally ejected from Blenheim Palace in 1933 — her dogs were spoiling the carpets and the duke disliked being threatened with a revolver — and having lost her own family fortune in the crash of 1929, she was portrayed by the press sadly cooking her supper alone in a glorious evening gown.

“Her Grace is strange,” said the duke’s lawyers in 1933, but they’d seen nothing yet. A decade later, Gladys had become a shabby, gun-toting recluse who hoarded her treasures (her glittering hoard was eventually sold for £784,000) within an increasingly derelict farmhouse shrouded in barbed wire.

Seemingly indestructible, she died in 1977, aged 96, after 40 years of self-willed obscurity. Hugo Vickers has ensured that Marlborough’s last duchess won’t return to obscurity any time soon by giving us this richly anecdotal and oddly captivating book.

The Sphinx: The Life of Gladys Deacon, Duchess of Marlborough, by Hugo Vickers, Zuleika, RRP£25, 388 pages

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