Is there any connection between Halloween and the crusaders? I remember hearing somewhere that a whole bunch of crusaders where executed on halloween or close to it. Is this true or am I just remembering something falsely?
Is it possible you are thinking of Friday the 13th?
In 1307, Philip IV of France, having feuded with the Knights Templar, eventually ordered many members of that order to be arrested. This mass arrest occurred on Friday the 13th, in October of that year (which is coincidentally close to Halloween - though it did not exist at the time, the closest thing was All Hallow's Eve). Though they had lost their last stronghold in the Levant in 1291 after the Siege of Acre, their vast estates across Europe provided them immense wealth. In Europe, the organization had taken on financial duties, serving as bankers and involving themselves in commercial enterprise. Philip instigated the arrests in order to seize their wealth, a desperate act, as he had already seized assets from Jewish and Lombard merchants previously in an attempt to alleviate a financial crisis born from costly wars.
King Philip had many knights tortured into making confessions of heretical activity, which was used as justification for their arrests. They were tortured, and many executed. Templar Grand Master Jacques de Molay was eventually burned at the stake in 1314.
Many popularly believe this incident is one of the reasons that Friday the 13th is considered unlucky.
Bibliography:
Medieval Warfare, Vol. 5, No. 1, Theme - Traitors in the Middle Ages (2015), p. 58, by Gareth Williams