The diamond necklace that lost Marie Antoinette her head

It is a story that involves two kings, a queen, a royal mistress, a cardinal, a confidence trickster and a prostitute. The plot is byzantine, including as it does forged letters, ingenious disguises, mistaken identities, opulent settings and an audacious theft. What became known as the Affair of the Diamond Necklace hastened, according to many historians, the French Revolution and was one of the reasons why Marie Antoinette was executed rather than exiled.

The story begins in 1772, when Louis XV commissioned an enormous diamond necklace for his maîtresse-en-titre, Madame du Barry. For 200,000,000 livres (about £12 million today), the royal jewellers Boehmer and Bassenge were to create a rivière consisting of 647 flawless, perfectly matched diamonds; a necklace so heavy that it would have to have diamond streamers down the back to prevent the wearer from toppling forward.

In 1774, Louis XV died. Undeterred, Boehmer and Bassenge completed the necklace and, in 1778, just after war had been declared on Britain, offered it to Louis XVI and Marie Antoinette. For whatever reason — Thomas Carlyle quotes the queen as saying ‘We have more need of seventy-fours [ships] than necklaces’ — she refused it.

For the next two years, Boehmer and Bassenge hawked the necklace around the royal courts of Europe without success. In 1781, following the birth of the dauphin, they again tried to sell it to Louis XVI — and again were rebuffed. This was the year in which Jeanne de Valois-Saint-Rémy, an impoverished and unscrupulous young woman, began to insinuate herself into royal circles by pretending to be one of Marie Antoinette’s closest confidantes. In 1783, she achieved her greatest social success when she was taken up by Cardinal de Rohan — nearly twice her age, extremely wealthy and, frankly, not that bright.

De Rohan had lost all chance of preferment, having publicly insulted Marie Antoinette’s mother. He yearned to be accepted back at court and de Valois offered to carry a letter of apology to the Queen. The forged response de Valois brought back was, unsurprisingly, encouraging. Further forged letters convinced de Rohan that the Queen was in love with him and that he should give money to de Valois, which he did. Her problem now was that the cardinal kept pressing for a meeting with sa Majesté. How relieved de Valois must have been when she encountered a prostitute, Marie Nicole Leguay d’Oliva, who bore an uncanny resemblance to the Queen and was willing, for a fee, to take part in a practical joke.

Late on August 11, 1784, d’Oliva, posing as the Queen, met de Rohan in the gardens of Versailles. D’Oliva gave de Rohan a rose, saying: ‘You know what this means’ — before fleeing.

It was enough.

The following January, de Valois had no trouble persuading de Rohan that Marie Antoinette wished to purchase the necklace in secret, with him acting as her intermediary. He made a downpayment and took delivery of the necklace, passing it to a man he believed to be the Queen’s servant, but who was working for de Valois.

When, the following July, the jeweller demanded the second payment, he explained Marie Antoinette had not yet sent him any funds. When the Queen was approached, naturally, she denied all involvement. At this point, Louis XVI insisted on a trial because, he claimed: ‘The dignity and virtue of the Queen were outraged.’ The cardinal’s crime was not theft, but his presumption that Marie Antoinette was the sort of woman who would make a secret assignation with a lover.

The Affair of the Diamond Necklace became a cause célèbre. De Valois and her co-conspirators were found guilty (with the exception of d’Oliva) of stealing the necklace and imprisoned. De Rohan was found innocent, but stripped of his offices and forced to sell his estates to pay for the jewel. Marie Antoinette was also ruined, because the public believed she really had purchased the necklace. As Napoleon later said: ‘The Queen’s death must be dated from the Diamond Necklace Trial.’

What of the necklace?

De Valois broke it up and sold the diamonds, probably to Robert Gray, a London jeweller. There’s a replica of it on display as part of Marie Antoinette Style, currently at the V&A Museum in London. The exhibition also includes the Sutherland Diamonds and the Anglesey Diamond Négligé Necklace, both of which almost certainly incorporate the best of the original gems.

This feature originally appeared in the March 11, 2026, issue of Country Life. Click here for more information on how to subscribe.