The Conciergerie, the prison where the Marquise de Brinvilliers was housed before her execution. Her trial exposed a hidden world of poisoners. Photo by Dietmar Rabich, CC BY-SA 4.0
The 17th century in France was marked by magnificence and turmoil, with the court of Louis XIV perfectly capturing this duality. Amidst the splendor of Versailles, a dark scandal unfolded—the Affair of the Poisons—that exposed a tangled web of aristocracy, poisoners, and alleged witches, shaking the very foundations of the French monarchy.
Origins of the Scandal
The affair began in 1675 with the trial of Marie-Madeleine-Marguérite d’Aubray, the Marquise de Brinvilliers, a noblewoman whose crimes shocked 17th century France. She was accused of conspiring with her lover, Captain Godin de Sainte-Croix, to systematically poison her father and two brothers, allegedly to secure her inheritance. Sainte-Croix, an alchemist with knowledge of toxic substances, had experimented with poisons for years, perfecting lethal mixtures. When he died unexpectedly, incriminating letters and poison vials were discovered in his possession, leading to Brinvilliers’ arrest. After fleeing to a convent in Liège, she was captured, tortured, and forced to confess before being publicly executed in 1676. Her trial sparked widespread paranoia, exposing a hidden world of poisoners and deepening suspicions within the aristocracy.
Unveiling the Network of Poisoners
In 1677, the arrest of Magdelaine de La Grange on charges of forgery and murder led to revelations about a clandestine network involved in poisonings and occult practices. Authorities detained numerous fortune tellers and alchemists suspected of selling “inheritance powders”—a euphemism for poison—to clients seeking to eliminate rivals or spouses.
The Role of La Voisin
At the heart of this chilling story was Catherine Deshayes Monvoisin, known as La Voisin, a midwife, fortune teller, and one of the most notorious figures in 17th century France. Operating from her Parisian home, she catered to the aristocracy, offering not only poisons but also mystical services, including divination and black masses—rituals allegedly performed to summon dark forces. Witnesses claimed that during these ceremonies, infants were sacrificed as part of satanic rites to secure favor, love, or power. Arrested in 1679, La Voisin admitted having sold poison and magical services to several members of the royal court. She also desribed the development of her career. The case fueled paranoia within the monarchy. She was burned at the stake in 1680, but the scandal did not end with her execution.
Implication of Madame de Montespan
One of the most sensational aspects of the Affair of the Poisons was the involvement of Françoise-Athénaïs de Rochechouart, known as the Marquise de Montespan and the chief mistress of Louis XIV. Accusations emerged suggesting that Madame de Montespan sought the services of La Voisin, a notorious fortune teller and poisoner, to maintain the king’s affection and eliminate romantic rivals. These services allegedly included purchasing aphrodisiacs and participating in black masses—rituals intended to invoke demonic forces to secure the king’s love.
Testimonies from individuals like Françoise Filastre, a servant to the late Duchesse de Fontanges, claimed that Madame de Montespan employed La Voisin to conduct black masses aimed at winning back the king’s favor. Additionally, Étienne Guibourg, a defrocked priest, purportedly officiated these ceremonies, which were said to involve infant sacrifices to bind the king’s affections.
Despite these serious allegations, concrete evidence was lacking. The charges were primarily based on confessions extracted under torture and the testimonies of dubious witnesses. Consequently, while the accusations tarnished Madame de Montespan’s reputation and caused a stir at court, they did not lead to her prosecution. The scandal highlighted the deep-seated fears and superstitions of the time, as well as the lengths to which individuals might go to secure power and affection in the treacherous environment of the French aristocracy.
The Chambre Ardente Tribunal
In response to the scandal, Louis XIV established the Chambre Ardente, a special tribunal, in April 1679 to investigate and prosecute those involved. Over three years, the tribunal held 210 sessions, issued 319 arrest warrants, and sentenced 36 individuals to death, including La Voisin, who was burned at the stake in 1680.
Impact on the Monarchy and Aristocracy
The Affair of the Poisons exposed the dark underbelly of the 17th century French aristocracy, revealing a society where intrigue and betrayal were rampant. It led to increased scrutiny of the nobility and a crackdown on occult practices. The scandal also prompted Louis XIV to distance himself from former favorites and tighten control over his court, aiming to restore the monarchy’s image.
The Poison Affair remains one of the most sensational episodes of the 17th century, highlighting the complexities and dangers of court life under Louis XIV. It serves as a vivid reminder of how ambition and desperation can intertwine, leading to actions that can shake even the most powerful institutions to their core.
