It’s Friday the 13th and, for the superstitious amongst us, that’s probably a reason to stay at home. This day has long been considered unlucky by many people. There is even a specific phobia associated with this inauspicious date (the easy to pronounce paraskavedekatriaphobia).

Across the years, there have been many disturbing events that have occurred on Friday the 13th. Is it coincidence, or is there something more sinister going on? Spoiler: It’s coincidence, but it’s still interesting.

Knights Templar

If you were a member of the Knights Templar in medieval France, then you would have had a good reason to worry about Friday the 13th. On that day in 1307, King Philip IV of France ordered the arrest of the Templars, an influential and extremely rich religious military order at the time.

Philip, otherwise known as Philip the Fair (for his good looks, certainly not his character) wanted to eliminate the order for financial purposes. The French crown had been in debt to the Templars for some time after borrowing money to help wage wars and cover other royal costs. By leveraging accusations of heresy and devil worship, Philip was able to justify arresting over 600 Templars who were tortured and eventually executed.   

The last leap of Sam Patch

On Friday November 13, 1829, spectators gathered at Genesee Falls, New York, to watch America’s first daredevil, Sam Patch, perform another death-defying stunt. For over two years, Patch had amazed audiences by leaping off incredible heights without incident. In September 1827, he had successfully leapt over the Passaic Falls in Paterson, which he followed by leaping off other waterfalls until he astounded onlookers at Niagara Falls in October 1829. However, his next exploit was to be his last.

According to eyewitnesses, when Patch leapt from Genesee Falls’ Upper Falls, his flight into the air did not look right. His diving posture was wrong, and rather than piercing the water, he hit it with an audible smack. His body did not return to the surface, which caused the crowd to panic. His frozen remains were eventually found four months later at the mouth of the Genesee River.

Black Friday bushfires

After several years of drought, high temperatures and strong winds led to bushfires that spread across Victoria, Australia, on Friday January 13, 1939. The Black Friday Bushfires, as they are now known, were part of a devastating bushfire season that had taken place across 1938 and into the new year. Around 75 percent of the state was affected by the fires as they burned almost 2 million hectares (4.9 million acres) of land. By the end of January, 71 people had lost their lives, around 1,300 buildings had been destroyed, and a total of 700 homes had been obliterated.

The Andes plane crash

The story of Uruguayan Air Force Flight 571 is one of the more distressing tales associated with Friday the 13th. In October 1972, the flight was carrying 45 passengers, including a rugby team, when it struck a ridge and crashed into the Andes mountains. Despite efforts to find the survivors, the harsh environment and poor weather forced the emergency rescue to be called off after eight days. Left with little food and dwindling options, the survivors were forced to resort to cannibalism to stay alive.

After 72 days stranded in the freezing conditions, 16 survivors were rescued following a grueling 10-day trek performed by two of the group who set out to find help.

Financial mini-crash

On Friday October 13, 1989, the stock market experienced a mini-crash when the Dow Jones Industrial Average fell by nearly 7 percent. The crash led to temporary financial panic, which earned the date the name “Black Friday”.

Costa Concordia disaster

On Friday January 13, 2012, the seven-year-old Costa Concordia cruise ship crashed and became stuck in shallow waters in the Tyrrhenian Sea, near Isola del Giglio. The disaster, which has been deemed completely preventable, has been blamed on the captain Francesco Schettino and his crew for irresponsible behavior after the ship sailed too close to the coast, at night, and at high speed.

In the end, over 4,000 people had to be rescued from the capsized vessel, while 32 people lost their lives.

Friday the 13th, what's all this fuss about?

The superstition surrounding Friday the 13th is old. Some believe the Templars' bloody fate started it, but it is likely older than that. In fact, the superstition is probably the outcome of various cultural beliefs, rather than any specific historical event. For instance, Christianity associates the number 13 with suspicion after Judas Iscariot, the 13th guest at the Last Supper, betrayed Christ.

In Norse mythology, the trickster Loki was the 13th guest at the banquet of the gods, which has been identified as setting off chaos as he arranged the death of Balder.

At the same time, the Bible itself is filled with other various unfortunate events that occurred on Fridays (most notably Good Friday, when Christ was said to have been crucified), which was believed to be an unlucky day more generally.

These cultural factors have likely influenced how we think about Friday the 13th, but our brains have probably done the rest: confirmation bias, the tendency to interpret information that agrees with our preconceptions. In this context, our minds have evolved to make links between potential causes and their effects. It’s helped us survive as a species, but sometimes it can go too far, making connections and adding meaning to random unrelated events.

So if you have a culture that sees Friday the 13th as an unlucky date, you’re likely to be more sensitive to unusual or negative events that occur on this date, even though terrible things happen on any other day as well.