So when the de Brinvilliers trial revealed that half of Paris was supposedly poisoning each other, Louis was like, everyone is gonna be investigated and held to account for this shit, even nobles. To show that he meant business, he wrote, “I shall submit myself to the rulings of this police and I intend that all shall respect and obey them as I will.”

Before we move on to some details that we had to cut for time, here’s a fun little quote about Madame de Brinvilliers’ relationship with Sainte-Croix:

It took her eight months to finish off her father .... To all his caresses and his affections, her only response was to double the dose .... She tried frequently to poison her husband, too, to be free to marry Sainte-Croix; but the latter, wanting no part of such a wicked woman, gave the husband counterpoison .... So that, after five or six doses of poison, and five or six doses of counterpoison-poisoned and then disempoisoned, batted back and forth between life and death, the poor man somehow managed to survive! 

The states of science, poison, fortune tellers, and the occult were all quite intertwined in those days. France was hot off the Renaissance, and recent legislation had widened the distribution of knowledge regarding chemicals. Though legend has it that poison was invented in Italy and brought to France by Catherine de’ Medici when she married Henry II in 1533, by the mid 1600s, there were many apothecaries both trained and untrained (and thus official and unofficial). Chemical knowledge had spread enough so that even those unofficial apothecaries were actually quite effective. Typically it was these amateaur apothecaries who also served as divineresses, mixing up love potions or even poisons. These ingredients weren’t hard to get ahold of: In those days, arsenic was used as common household rat poison. Though science had advanced, it was still quite connected to religion; crosses and amulets were used in conjunction with spells and potions, though it was against the Catholic Church’s preachings by that point. Just as often, it seems, black masses were performed. 

Now onto the mistress of the hour, the Marquise de Montespan. Though she’d married a Marquis in 1663, his family had lost its wealth, and he hadn’t adjusted his spending accordingly. They had two children together before the marriage fell apart, and Montespan returned to court with her sights set on the top spot on the mistress charts. (Ironically, her role at court was a lady-in-waiting to the queen… rude.) At first, her best attempts didn’t catch the king’s eye. One member of court recounted: “[b]eautiful as she was, and witty, quick at repartee and banter, she had not at first appealed to the King. He even went to so far, one day, at table with Monsier his brother, as to jest about her efforts to attract him. ‘She tries hard,’ he is supposed to have said, ‘but I am not interested.’” Within a year, though, the king had knocked up both his wife and his main squeeze, Louise de la Valliere, and so there was an availability in his bed. Soon, Montespan too was pregnant by the king, but by that point she had also won his heart. She reportedly could always make him laugh. Montespan legally separated from her husband and even got her dowry back (she saved it for their children). The seven children she had by Louis XIV were legitimized as heirs to the throne. But after that seventh child was born, the king’s eye began to wander again. Montespan felt threatened by the younger woman he became involved with, Mademoiselle de Fontages (she whose room was destroyed by bears). In 1680, as the investigation into the Affair of the Poisons was still unfolding, de Fontages had a miscarriage from which she never fully recovered. For months, her ill health dragged on, and she voiced suspicions that she had been poisoned.

One of those admirers had been the “sorcerer” Lesage, real name Adam de Coeuret. He wore gray clothing and a reddish wig, but was nonetheless reportedly charming. His relationship with la Voisin took a turn after he began stealing business from her, and in retribution she turned him into the authorities. After he was found guilty, he served a few years of penance in the galleys of naval ships before returning to Paris and resuming his old trade, even occasionally working again with la Voisin (they kept it platonic this time). After la Voisin was arrested by la Reynie, it wasn’t long before Lesage was arrested as well. After that, the records of their interrogations are a regular tit for tat, with one placing blame on and revealing information about the other, despite their shared history. It became clear that each of them had been involved with some high-ranking aristocratic clients, including the Marechal-Duc de Luxembourg, one of France’s foremost generals, and the Comtesse de Soissons, a longtime friend of the king’s. As Somerset puts it, this “caused chaos and stupefaction almost without compare.” While de Soissons and others were given time to flee France, Luxembourg voluntarily turned himself in, was arrested, and held in the Bastille like a common prisoner. Though Luxembourg was tried, he was acquitted and a year later brought back to his role as Captain of the Guard.

As The Professor shared, once la Reynie got too close to Mme de Montespan, Louis XIV called the whole thing off. As his secretary of state Jean-Baptiste Colbert said, "If all the people who had gone to have their fortunes told or to purchase good-luck charms were to be brought to trial, the century would not be long enough to see the end of the affair!” It was just too big and too stupid. Louis XIV issued an edict, fantastically named Edict for the Punishment of Different Crimes, that made it clear that magic was fake, and I really love some of its wording:

There is a surprising number of ignorant and gullible people who were engaged with vain curiosities and passing superstitions, superstitions that are impious and sacrilegious. And with a fatal leak of engagements, those who have the most evidence against the conduct of these deceivers should bring the criminal to the end of the spell, turning them in, and add the poison to the list of impious and sacrilegious. With these practices having come to our knowledge, we will employ all possible means to make it stop, and stop by suitable means, stop the progress of these detestable abominations.

Once la Reynie’s commission was disbanded, those who were still in jail mostly either received minor sentences or were just released; but others, like Lesage, received lifetime sentences (still better than burning at the stake like his ex, la Voisin). La Reynie was kind of bummed that after all that it kind of fizzled out, which tbh I get. He continued on in his role as chief of police for a few more decades and died in 1709.