I often use real historical events as inspiration for my stories: To Catch an Earl’s plot draws inspiration from the amazing real-life theft of the French Crown Jewels from Paris in 1792. Emmy Danvers, my heroine, is an audacious jewel-thief heroine whose mission is to locate and steal back the French crown jewels for the glory of France – in particular one large blue diamond known as the ‘Bleu du Roi’ or ‘French Blue’, which ended up, hundreds of years later, as the Hope diamond . . .

The ‘French Blue’: From ‘Tavernier blue’ to ‘French Blue’ to ‘Hope Diamond’.

Our story starts with the 17^th century trader and adventurer Jean-Baptiste Tavernier, who purchased a 112 carat blue diamond on his travels in India: probably at the old diamond workings at Kollur, in the modern Indian Province of Andhra Pradesh.

He returned to France and sold that gem to Louis XIV for the sum of 220,000 livres of French money, the equivalent today of 147 kilograms of pure gold (plus, it is rumored, a patent of nobility, the cost of which was approximately 400-500,000 livres at the time. It is unlikely to be a coincidence that a year after he sold Louis the great blue diamond, Tavernier purchased a chateau in the Duchy of Savoy near Lake Geneva and became Baron of Aubonne!)

In 1691, Louis XIV commissioned his court jeweler, Jean Pitau, to recut Tavernier’s great blue diamond. The result was a much enhanced, brilliant, sixty-nine carat gem, which Colbert named “le diamant blue de la couronne de France,” or simply the ‘French Blue.’ 

In 1749 Louis XV had the stone reset as part of the great ceremonial insignia of the Order of the Golden Fleece (Toison d’Or), along with the Côte de Bretagne spinel (a red stone, cut into the shape of a dragon) and the Bazu diamond.

The Medal of the Order of The Golden Fleece with (top to bottom) The Bazu Diamond, The Côte de Bretagne spinel and The French Blue diamond.

Then came the French Revolution. After the insurrection of 10 August 1792, the French Crown Jewels were confiscated from King Louis XVI by the revolutionaries of the French National Assembly and deposited in the royal storehouse known as the Garde-Meuble. The door was sealed and guards were rotated daily. Unfortunately, there were problems with these safety measures: First, because of the seal on the door, guards could not patrol inside the room, and, second, guards often left the room unguarded.

On the morning of 17 September 1792, three commisioners at the Garde Meuble discovered a robbery had taken place there the previous night. Thieves had climbed up the building’s colonnade facing the Place Louis XV and gained access through a window. Once inside, they had broken the seals on eleven cabinets containing the Royal Crown Jewels, as well as the State and coronation regalia.

The State and coronation regalia was, from a historical point of view, priceless: the Charlemagne crown; Louis XV’s 1722 coronation crown; the 60-cm medieval gold sceptre of Charles V; the ivory-hand-topped gold sceptre called ‘le main de justice’; the Ampulla; the coronation sword (Joyeuse). Other items orbs, onyx chalices and assorted historic relics were almost as valuable.

Stored with the regalia was a jewel-thief’s dream: the enormous collection of gemstones gathered over decades by the Kings of France. A 1791 inventory commissioned by the National Assembly listed 9,547 diamonds worth 21-million francs. Among these diamonds were the Regent (a 140.5-carat brilliant-cut white diamond sold in 1717 to Philippe, duc d’Orleans valued at 12-million francs), the Sancy (a pale-yellow 55-carat diamond sold around 1695 to Louis XIV valued at 1-million francs) and the Hortensia (a pale orange-pink 20-carat diamond which later got its name from Hortense de Beauharnais, Queen of Holland and daughter of Empress Josephine). Also included in the collection was the Ruspoli Sapphire a 135-carat lozenge-shaped sapphire bought by Louis XIV, and the French Blue (set in the Order of the Golden Fleece).

Modern sources conflict, but it appears at least six men participated in the robbery, (police officials suspected one or more of the commissioners were in on the conspiracy as well). Historian Richard Kurin even speculated that the “theft” was in fact an ‘inside job’ engineered by the revolutionary leader Georges Danton as part of a plan to bribe an opposing military commander, Duke Karl Wilhelm of Brunswick to support Napoleon. While this is unlikely to be true, I decided to play the ‘what if?’ game and used this idea in the plot of To Catch An Earl. I imagine that Danton’s son becomes obsessed with finding the gems that The Nightjar has stolen from him – and ends up bribing Emmy to get them. But I digress…

So what happened to the gems?

Most of the larger gems were quickly recovered, thanks to confessions, police informers and at least one anonymous tip-off. The Regent and the Hortensia diamonds were recovered in 1793. One of the condemned men, Depeyron, begged to be spared the scaffold in return for the surrender of his spoils; escorted to his home in a dead-end street called Sainte-Opportuné, he opened the roof window, reached out and handed back to the authorities a bag containing a number of prize gems – including the famous Hortensia and Grand Mazarin diamonds. A second stash was recovered in the allée des Veuves (avenue Montagine) where it had been buried by Badarel. The fabulous 13-caret Regent diamond was supposedly discovered in an attic. Other major diamonds  – the Sancy and the Guise – were located in the house of a man named Tavenal.

But the thief who had taken the Golden Fleece, a man named Cadet Guillot, had left Paris and traveled to Le Havre and then to London. What happened next is unclear. At some point the Toison d’Or was broken up and the diamonds sold. In 1796 Guillot returned to the Continent but fell foul of one of his fellow-conspirators and was consigned to a debtors’ prison. The French Blue disappeared from sight.

Napoleon Bonaparte, now in power, became determined to track down the missing French Crown Jewels. He offered rewards for any information that would lead to their recovery. It is likely that the Bleu Du Roi was recut at this time, in an attempt to disguise it.

French law includes a statute of limitations of 20 years on stolen property, whereby a person cannot be charged with a crime if it’s older than 20 years. It is unlikely to be coincidence that in 1812, a mere TWO DAYS after the statute of limitations for recovering stolen property had expired on the Crown Jewels theft, London jeweler John Francillon sold a 45.5-carat deep blue diamond to diamond merchant Daniel Eliason.

It was suspected at the time the new stone was the stolen and re-cut French Blue, but Francillon had documents to prove he was legally its owner. It is unclear from whom Francillon purchased the gem. Eliason tried for many years to sell the diamond, but to no avail. 

Finally, in 1830, the stone was purchased by a rich London banker, Anglo-Dutch financier Henry Philip Hope, who paid between $65,000 and $90,000 in that day’s 

Currency, and thereby gave the diamond its name.

The rest of the story has been told many times. The diamond passed through the Hope family who sold the diamond in 1901 to pay off debts. It passed through the hands of several dealers to Cartier. From there it went to Evelyn Walsh McLean, jeweler Harry Winston, and finally to the place in which it now resides, the Smithsonian Institution in Washington, D. C.

So is the Hope Diamond really The French Blue?

Yes. It had long been believed that the Hope Diamond had been cut from the French Blue, but confirmation finally happened recently when a three-dimensional lead model of the latter was rediscovered in the archives of the national Museum of National in Paris in 2005.

Previously, the dimensions of the French Blue had been known only from two drawings made in 1749 and 1789; although the model slightly differs from the drawings in some details, these details are identical to features of the Hope Diamond, allowing CAD technology to digitally reconstruct the French Blue around the recut stone. 

How does this fit in with To Catch An Earl?

To Catch An Earl takes place in 1816 – at a time when the whereabouts of the French blue are undocumented. In the story, I’ve imagined that the diamond dealer Eliason, unable to sell the stone and unwilling to keep it on his own premises, has temporarily donated it to the British Museum for display and safekeeping. It’s from here that Emmy ‘liberates’ it! I like to think that this idea fits in with the unknown location of the Bleu du Roi at this time. Of course, at the end of the book the jewels are returned (secretly) to the French by the Prince Regent, which didn’t happen in real life at all, but I like to give them this fictional Happily Ever After!

 And the other jewels – what happened to them?

After Napoleon’s abdication in 1814, Marie-Louise took the Regent diamond back with her when she returned to Vienna. Her father, Emperor Francis I of Austria, later returned it to France.

In 1828, the Sancy diamond finally turned up and was sold by a French jeweler to Prince Anatole Demidoff, a Russian aristocrat. It was renamed the Demidoff and was given to his wife, Princess Mathilde. In 1906, the Astor family purchased the Sancy; in 1978, Viscount Astor sold it to the Louvre for a reported $1-million.

Want to read more?

References: Here’s a good in-depth blog post about the actual theft: http://rodama1789.blogspot.com/2018/09/the-theft-of-crown-jewels-in-september.html

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