There are many theories as to why many of us consider Friday the 13th to be an inauspicious day, but the most common seems to relate back to the day, Friday, October 13, 1307, when France’s King Philip IV (also known as “Philip the Fair”, which is sort of odd, considering) had the Knights Templar rounded up and imprisoned.
The Knights Templar was a legendary order of “warrior monks” formed during the Christian Crusades to combat Islam. Known as a fighting force for more than 200 years,
“…by the 1300s the order had grown so pervasive and powerful it was perceived as a political threat by kings and popes alike and brought down by a church-state conspiracy, as recounted by Katharine Kurtz in Tales of the Knights Templar (Warner Books, 1995):
On October 13, 1307, a day so infamous that Friday the 13th would become a synonym for ill fortune, officers of King Philip IV of France carried out mass arrests in a well-coordinated dawn raid that left several thousand Templars — knights, sergeants, priests, and serving brethren — in chains, charged with heresy, blasphemy, various obscenities, and homosexual practices. None of these charges was ever proven, even in France — and the Order was found innocent elsewhere — but in the seven years following the arrests, hundreds of Templars suffered excruciating tortures intended to force “confessions,” and more than a hundred died under torture or were executed by burning at the stake.
There are problems with the “day so infamous” thesis, not the least of which is that it attributes enormous significance to a relatively obscure historical event. Even more problematic for this or any other theory positing pre-modern origins for a superstitious dread of Friday the 13th is the fact that so little documentation has been found to prove that such a superstition even existed prior to the late 19th century.”
Interesting. In any case, I’m not walking under any ladders today.
Excerpted in part from: http://urbanlegends.about.com/cs/historical/a/friday_the_13th_4.htm
With other info available at: http://www.beyond.fr/history/templars.html