April Fools has its origins in France in 1563, when they decided at the council of Trent to switch to the Gregorian calendar, the system that we use today. It took until 1582 for it to come into effect and override the Julian Calendar, which saw the year begin around the start of April. This change took a while for the population to get used to, but eventually, after most of the populace had made the change, people who still used the Julian calendar where made fun of and would have pranks and jokes pulled on them on April 1st, which is where this holiday began.
people who still used the Julian calendar where made fun of and would have pranks and jokes pulled on them on April 1st, which is where this holiday began.
There is also an idea that ancient Rome had a similar tradition around the end of March which translated itself into April Fools. This was because the cult of Cybele would play pranks and jokes on unsuspecting civilians while dressed in costumes.
The holiday became popular in Britain in the 18th century and more so in Scotland as they, for many years, celebrated the holiday with a two day festival.