There is a lot of conjecture as to how we came to serve pranks on this day. Was it when the Gregorian calendar changed over from the Julian in the 1500’s, confusing farmers on the proper day to start summer planting? A Roman winter festival? A Celtic spring festival? None of the above? All of the above?
Or was it Geoffrey Chaucer’s rooster Chauntecleer, who is tricked by a fox “Since March began, full thirty days and two,” that is, the 32nd day from 1 March, which is 1 April. Except that the numbers don’t add up when in the “Nun’s Priest’s Tale” it states that the story takes place on the day when the sun is “in the sign of Taurus had y-rune Twenty degrees and one,” which would not be 1 April.
Some historians suggest that April Fools’ originated because, in the Middle Ages, New Year’s Day was celebrated on 25 March in most European towns, with a holiday that in some areas of France ended on 1 April, and those who celebrated New Year’s Day on 1 January made fun of those who celebrated on other dates by the invention of April Fools’ Day. But that’s not a certainty either.
Or was it in 1686. John Aubrey, a British philosopher, referred to the celebration as “Fooles holy day”, the first British reference. On 1 April 1698, several people were tricked into going to the Tower of London to “see the Lions washed”.
Or this (it always comes down to blaming the Jews, doesn’t it?) The “Public Advertiser” for April 13, 1789, contains the following paragraph:
“Humorous Jewish Origin of the Custom of Making Fools on the First of April.—This is said to have begun from the mistake of Noah in sending the Dove out of the Ark before the water had abated, on the first day of the month among the Hebrews, which answers to the 1st of April; and to perpetuate the memory of this deliverance it was thought proper, who ever forgot so remarkable a circumstance, to punish them by sending them upon some sleeveless errand similar to that ineffectual message upon which the bird was sent by the Patriarch. The custom appears to be of great antiquity, and to have been derived by the Romans from some of the Eastern nations.” — William Ralston Balch
Of course, in the Hebrew calendar, the month of Nisan corresponds to March or April, since this calendar is a lunar calendar and all feasts are moveable.
The fact of the matter is, no one knows for sure.
So, to sum it all up, I think it is only a fool who believes these origins of April Fool’s Day. Just fool around today. Heck, fool around every day.