“In all likelihood, April Fools’ Day [grew] out of one or more festivals celebrated around the vernal equinox, like the Roman festival of Hilaria, a day of joy marked by games, amusements and masquerades.

“Some scholars point out that April Fools’ Day could be much older. The 13th day of the Persian new year is called Sizdah Beda, and falls on or around April 1 each year. As part of the festivities, some Iranians pull pranks on each other, a tradition that could go back more than 2,500 years.

“Whatever its beginnings, April Fools’ Day is clearly a holiday that resonates with people, regardless of geography… Today, it’s celebrated across the globe.”

~ Edgar B. Herwick III
The Curiosity Desk
WGBH News, April 1, 2013