François Prelati

François Prelati was an Italian cleric and alchemist who took part in the murders committed by Gilles de Rais in the 15th century. He claimed he could summon demons and involved Gilles in this practice.

He is thought by some to have been a possible sexual partner of Gilles  but "in absence of evidence",  this is only a speculation initially stated by Georges Bataille.

Life
Sentenced to life imprisonment following the trial of Gilles de Rais, François Prelati probably managed to escape, and then found refuge outside the jurisdiction of the Duchy of Brittany, more precisely at the court of Duke René of Anjou. This prince, son of Yolande of Aragon, had become the titular king of Sicily and the new head of the House of Valois-Anjou following the death of his elder brother Louis III of Anjou. Through the intermediary of a confessor of the "Good King René", whose sumptuous and refined court welcomed many artists and poets, the young Italian cleric obtained an audience with the Angevin prince.

Prelati was able to show off his alleged alchemical talents, probably thanks to conjuring tricks that enabled him to brandish an ingot of silver concealed in the crucible of the "magnum opus" at just the right moment, so much so that the swindler was appointed captain of La Roche-sur-Yon castle by René of Anjou. Adopting the identity of François de Montcatin (after the name of his native town), the Tuscan adventurer used his new position to seek revenge on Geoffroy Le Ferron (now Treasurer of France) because of the legal troubles following Gilles de Rais' act of force in Saint-Étienne-de-Mer-Morte.

On his way to Taillebourg to visit Prigent VII de Coëtivy (Admiral of France and husband of Gilles de Rais' only daughter), Geoffroy Le Ferron passed through La Roche-sur-Yon on 7 December 1444. Invited to the castle by the captain-alchemist, he was insulted by the priest Eustache Blanchet, before being arbitrarily imprisoned by order of Prelati, who blamed him for his own imprisonment in Nantes during the trial of Gilles de Rais. In order to extort an enormous ransom from the treasurer, Rais' two former servants subjected him to two and a half months of harsh treatment. Among other moral and physical tortures, Prelati and Blanchet try to frighten Le Ferron by pretending to discover among his papers a dummy letter that compromises him in an imaginary betrayal by Prigent de Coëtivy.

Informed of the situation, René of Anjou's officers demanded that Prelati bring Le Ferron before the ducal council. The captain pretended to comply, before returning the French treasurer to his dungeon. Twelve days later, knight Guy d'Aussigny, lord of Trèves and lieutenant to the king "in the countries of Poitou, Saintonge, the government of La Rochelle and Angoumois", appeared with a company of fifty men-of-war in front of La Roche-sur-Yon's fortress. Refusing to deliver Geoffroy Le Ferron, Prelati opposed the surrender of the fortress and marched out with his own troops, provoking a skirmish that resulted in the death of one of Guy d'Aussigny's soldiers.

Shortly afterwards, two of René of Anjou's officers tried again to get Prelati to hand over Geoffroy Le Ferron. The Italian captain finally agreed, after paying the French treasurer's ransom. The latter was transferred to Angers, where he unsuccessfully lodged a complaint with the Chamber of Audit of Anjou. Le Ferron managed to be escorted to King René d'Anjou in Nancy, but remained in custody there for some time, where King Charles VII of France was staying at the time. When the French King heard of the affair, the matter was referred to the Parlement of Paris, which finally issued a ruling condemning Prelati and his main accomplice, squire Jacques Chabot, to death. Towards the end of March 1446, or at the beginning of the following month, Prelati was burned at the stake to atone for his crimes.

Referred to the Parlement of Paris along with several other Prelati's accomplices, Eustache Blanchet was in constant default from January 1448 to March 1451. On 18 May 1453, the Parliament handed down its final ruling, condemning the priest and his acolytes to return Geoffroy Le Ferron's property, to make amends to the King and the Treasurer of France, and to pay a fine, perpetual banishment and confiscation of their property.

In fiction
François Prelati appears as a recurring character in the French comic series Jhen Roque written by Jacques Martin. Comic artist Jean Pleyers depicts him as "an extremely handsome young man with black hair and a black suit, who doesn't mind posing as Saint Sebastian for his painters friends."

Prelati has also appeared in stories such as Thief of Souls by Ann Benson and Fate/strange fake by Ryōgo Narita., as well as a character referencing him in the anime Senki Zesshou Symphogear AXZ and Fate/Zero.