April Fools’ Day—celebrated on April 1 each year—has been celebrated for several centuries by different cultures, though its exact origins remain unclear.
While its exact history is a bit of a mystery, some historians believe that April Fools’ Day dates back to 1582, when France switched from the Julian calendar to the Gregorian calendar (illustrated below), as called for by the Council of Trent in 1563.
In the Julian Calendar, as in the Hindu calendar, the new year began with the spring equinox around April 1.
People who were slow to get the news or failed to recognize that the start of the new year had moved to January 1 and continued to celebrate it during the last week of March through April 1 became the butt of jokes and hoaxes and were called “April fools.”
These pranks included having paper fish placed on their backs and being referred to as “poisson d’avril” (April fish), said to symbolize a young, easily caught fish and a gullible person.
Historians have also connected April Fools’ Day to festivals such as Hilaria (Latin for joyful), which was celebrated in ancient Rome at the end of March by followers of the cult of Cybele.
It involved people dressing up in disguises and mocking fellow citizens and even magistrates and was said to be inspired by the Egyptian legend of Isis, Osiris and Seth.
