Why April Fools Day in France Involves Fish Pranks

If you find yourself in France on April 1, don’t be surprised if something seems fishy. Maybe someone gives you a chocolate or a pastry in the shape of a cod? Perhaps you find a paper haddock stuck to your back, and then everyone erupts into laughter and starts pointing and shouting “poisson d’avril”? Don’t be alarmed, you’ve simply immersed yourself in the centuries-long French tradition of April Fool’s Day, known as poisson d’avril or “April Fish.”

“The idea of April Fool’s Day, or April 1, as a special day is murky,” says Jack Santino, a folklorist and Professor Emeritus at Bowling Green State University in Ohio. “Every country has its own historical event they think gave rise to it.” But France’s tradition is the only one that involves aquatic life. Historians have many theories about the origins of this piscine tradition, but no overall consensus. The most common theories are connected to pagan celebrations of the vernal equinox, Christianity, a 16th-century calendar change, and the start of the French fishing season.

Some historians date this tradition back to the Ancient Roman pagan festival of Hilaria, a celebration marking the vernal equinox with games and masquerades. Santino says ancient Roman and Celtic celebrations of the vernal equinox are likely forerunners. Connections to those rituals “provide a kind of cultural vocabulary that people can draw on,” according to Santino. However, he believes they probably don’t have a direct connection to the fish part.

For some, that’s where Christianity comes in. The “ichthus” fish—an ancient Hellenic Christian acronym for “Jesus Christ, Son of God, Savior”—is nowadays widely recognized as a symbol of Christianity, but was originally used as a secret marker of Christian affiliation. Moreover, the Lenten forty-day period between Ash Wednesday and Easter Sunday prohibits the consumption of meat, so fish is often served as a substitute protein during this period.

As the end of Lent often occurs on or near April 1, celebrations including fish imagery would be apt to mark the end of the fasting season. Some even go so far as to surmise that poisson d’avril is a corruption of the word “passion,” as in “passion of the Christ,” into “poisson,” the French word for fish. Despite these cultural associations, Santino points out there is no actual evidence for this link to Christianity.

Then there’s the popular calendar change theory that has been widely discounted by experts today, but still comes up. In 1564, King Charles IX of France issued the Edict of Roussillon, which moved the start of the calendar year from somewhere in the period of March 25 and April 1 (different provinces kept their own calendars) to January 1.

Pope Gregory XIII standardized January 1 as the beginning of the calendar year throughout the entire Christian empire with the adoption of the Gregorian calendar in 1582. One might surmise that those who still observed the start of the new year on April 1 rather than January 1 were the “April Fools” in question and therefore subject to pranks. However, references to poisson d’avril predate the 1564 edict, occurring in print as early as 1466, which debunks this explanation.

Another plausible theory involves actual fishing. As the days get longer in the northern hemisphere, the return of spring also marks the beginning of the fishing season in France, on or near the first day of April. Some posit that the prank of offering a fish was to tease fishermen who, at this time, either had no fish or an incredible abundance. They would either have to wait around for spawning fish to be of legal size before catching them or, once it was finally time, they would be overwhelmed by catching so many fish rushing upstream. According to this theory, real herrings were the original sea critter of choice for the prank, and the trick was to hook a dead herring onto a fisherman’s back and see how long it took him to notice, as the fish began to progressively stink over the course of the day.

The poisson d’avril tradition took another turn in the early 20th century, when friends and lovers would exchange decorative postcards featuring ornate images of fish. The majority of these cards were inscribed with funny rhyming messages that were often flirtatious and suggestive, but cloaked in humor. While most cards depict young women, flowers, and fish, the ocean and other marine animals are occasionally featured, as well as references to advances in technology, such as airplanes and automobiles. Pierre Ickowicz, chief curator of the Château de Dieppe Museum in Normandy, which houses an impressive collection of these cards, says the card exchange tradition seems to have died out shortly after World War I. The museum’s 1,716 postcards are mainly from the 1920s-1930s.

These days in France, the most common observers of poisson d’avril are schoolchildren, who delight in taping paper fish to the backs of their siblings, classmates, and teachers. Although the execution has varied over time, from dead herring accessories to postcards to paper fish, the prankster nature has been consistent.

“This idea of playing pranks on people is something that would be obnoxious if it weren’t socially condoned on certain days,” says Santino. He notes that times of transition are often connected to rites of passage where societal rules can be broken. “If poisson d’avril has to do with a recognition of springtime, I would link it to the idea of a celebratory transition into a new period of time, and part of that celebration means we can do things that are not usually allowed.”

Today, people celebrate poisson d’avril in both neighboring Italy and in Quebec, Canada, a former colony of France. The exact origins remain murky, but the fish endures. Whether or not you participate in any kind of trickster behavior on the first of April, there’s surely some relief today that an actual dead, stinky fish is no longer a regular part of April Fool’s day—or at least hopefully that bit of history doesn’t plant any devilish ideas.