Friday the 13th didn’t start from one single event; it’s a mash‑up of older fears about Fridays , the number 13 , and then some modern storytelling that glued it all together into today’s superstition.

How did Friday the 13th come about?

1. Two separate “unlucky” ideas that merged

For centuries in Europe, both Fridays and the number 13 carried uneasy reputations on their own.

  • Fridays were seen as unlucky in Christian tradition because Jesus was crucified on a Friday, and some medieval beliefs warned against starting trips or new ventures that day.
  • The number 13 broke the “perfect” pattern of 12 (months, zodiac signs, apostles, Olympian gods), so it felt off‑balance or chaotic.
  • Over time, these two strands — wary Fridays and suspicious 13s — were combined in popular belief into one especially ominous date: Friday the 13th.

2. Mythic and religious roots (but no single “origin moment”)

People often point to legendary or religious stories to explain why 13 feels wrong, but historians see these more as later explanations than hard origins.

  • Norse myth: A famous story tells of 12 gods feasting in Valhalla when Loki, the trickster, arrived uninvited as the 13th guest and caused the death of the beloved god Balder, bringing grief to the world.
  • Christian story: At the Last Supper, Jesus and his 12 disciples made 13 at the table, and Judas — often treated as the “13th guest” — betrayed Jesus, who was then crucified on Friday.
  • These tales helped people retro‑explain why 13 and Fridays “feel” unlucky, but there is no proof that medieval Europeans were already focused specifically on “Friday the 13th” as a single cursed date.

3. The Knights Templar story (famous, but debated)

One of the most dramatic stories tied to Friday the 13th is historical, but its link to the superstition is probably modern.

  • On Friday, 13 October 1307, King Philip IV of France ordered the mass arrest of the Knights Templar, a powerful religious‑military order; many were later tortured and executed.
  • Some modern writers claim this brutal crackdown is the “real” origin of Friday the 13th being unlucky.
  • Folklorists who trace written sources, however, find little evidence that people at the time immediately turned that date into a long‑lasting popular superstition; the strong connection seems to be emphasized mainly in recent centuries and especially in 20th‑century retellings.

4. When did people actually start saying “Friday the 13th” is unlucky?

The specific phrase “Friday the 13th” as a cursed date appears surprisingly late in the historical record.

  • Researchers find that fear of the number 13 goes back many centuries, and wariness of Fridays also shows up in medieval and early modern sources.
  • But clear references to Friday the 13th itself being unlucky don’t show up until the 1800s, especially in French and then American plays, newspaper pieces, and popular culture.
  • By the late 19th and early 20th century, the idea was widespread enough that writers could joke about people refusing to travel, sign contracts, or do business on that day.

5. How modern media supercharged the superstition

The superstition became global pop culture in the 20th century, thanks to fiction, news, and cinema.

  • In 1907, Thomas W. Lawson’s novel “Friday, the Thirteenth” used the date as the setting for a stock‑market scheme, making the phrase eye‑catching in finance and newspapers.
  • Throughout the 1900s, stories about disasters falling on Friday the 13th (like plane crashes or bombings) were highlighted as “proof” of the date’s bad luck, reinforcing the belief each time it came around.
  • The horror film franchise “Friday the 13th,” launched in 1980, turned the date into a brand of fear, embedding it deeply into global pop culture and giving rise to endless trivia, discussions, and “spooky” marketing whenever the date appears on the calendar.

6. Today: fear, fun, and a bit of economics

In 2026, Friday the 13th functions as both a superstition and a kind of cultural event.

  • Some people genuinely experience anxiety tied to the date, a phenomenon sometimes called paraskevidekatriaphobia (fear of Friday the 13th), and surveys estimate that tens of millions in the U.S. at least consider it unlucky.
  • Economists and journalists often note that travel bookings, big purchases, or business activity can dip slightly on these Fridays because people postpone plans, which can cost the economy millions.
  • At the same time, many others treat it as a playful “spooky” mini‑holiday, binge‑watching horror movies, sharing memes, or even claiming it as a lucky day — illustrating how the date now lives somewhere between genuine fear, ironic fun, and internet trend.

7. Key viewpoints on how it really started

There isn’t one agreed‑upon answer to “how did Friday the 13th come about,” but scholars and storytellers tend to fall into a few camps.

  • Historical‑blend view: The superstition emerged gradually from older European fears about Fridays plus 13, solidified in the 19th century as people explicitly started talking about Friday the 13th.
  • Templar/Last Supper view: Popular books and films emphasize dramatic stories like the Knights Templar arrests in 1307 and the Last Supper to give the superstition a vivid narrative origin.
  • Pop‑culture magnifier view: Modern media — novels, newspapers, horror films, and now online forums and social platforms — massively amplified the belief, turning what may have been a niche superstition into a global “brand” of bad luck.

Mini HTML table of the main threads

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Element Why it mattered When it took shape
Unlucky Fridays Linked to Jesus’s crucifixion and general folk warnings about starting tasks on Friday.Medieval Europe and later.
Unlucky 13 Disrupts the “perfect” 12; reinforced by myths like Loki as the 13th guest and the 13 at the Last Supper.Antique and medieval beliefs, refined over time.
Friday 13 October 1307 Arrest of the Knights Templar later retold as a key unlucky “Friday the 13th.”Event in 1307; superstition tie‑in emphasized much later.
19th‑century plays & press Spread the specific idea that “Friday the 13th” itself is a bad‑luck date.1800s.
20th‑century books & films Novels and the “Friday the 13th” horror franchise made the date iconic worldwide.1900s onward.

Information gathered from public forums or data available on the internet and portrayed here.