[Bilge_Rat]

Apparently, the tradition of Friday the 13th being an unlucky day goes back to Friday, October 13th, 1307 when the King of France ordered the arrest of the leadership of the Knights Templar. The King owed large amounts of money to the order and layed false charges of heresy to get out of repaying. Many were burned at the stake and the order was dissolved:

At dawn on Friday, 13 October 1307 (a date sometimes linked with the origin of the Friday the 13th superstition)[37][38] King Philip IV ordered de Molay and scores of other French Templars to be simultaneously arrested. The arrest warrant started with the phrase: "Dieu n'est pas content, nous avons des ennemis de la foi dans le Royaume" ["God is not pleased. We have enemies of the faith in the kingdom"].[39] Claims were made that during Templar admissions ceremonies, recruits were forced to spit on the Cross, deny Christ, and engage in indecent kissing; brethren were also accused of worshipping idols, and the order was said to have encouraged homosexual practices.[40] These allegations, though, were highly politicised without any real evidence.[41] Still, the Templars were charged with numerous other offences such as financial corruption, fraud, and secrecy.[42] Many of the accused confessed to these charges under torture (even though the Templars denied being tortured in their written confessions), and their confessions, even though obtained under duress, caused a scandal in Paris. The prisoners were coerced to confess that they had spat on the Cross: "Moi, Raymond de La Fère, 21 ans, reconnais que [j'ai] craché trois fois sur la Croix, mais de bouche et pas de cœur" ["I, Raymond de La Fère, 21 years old, admit that I have spat three times on the Cross, but only from my mouth and not from my heart"]. The Templars were accused of idolatry and were suspected of worshiping either a figure known as Baphomet or a mummified severed head they recovered, amongst other artifacts, at their original headquarters on the Temple Mount that many scholars theorize might have been that of John the Baptist, among other things.[43]

Relenting to Phillip's demands, Pope Clement then issued the papal bull Pastoralis praeeminentiae on 22 November 1307, which instructed all Christian monarchs in Europe to arrest all Templars and seize their assets.[44] Pope Clement called for papal hearings to determine the Templars' guilt or innocence, and once freed of the Inquisitors' torture, many Templars recanted their confessions. Some had sufficient legal experience to defend themselves in the trials, but in 1310, having appointed the archbishop of Sens, Philippe de Marigny, to lead the investigation, Philip blocked this attempt, using the previously forced confessions to have dozens of Templars burned at the stake in Paris.

https://en.wikipedia.org/wiki/Knight...nd_dissolution