April Fool's Day Falls on the First Day of April.

"The first of April is the day we remember
what we are the other 364 days of the year."
- Mark Twain

 Some believe April Fool's Day sort of evolved simultaneously in several cultures at the same time, from celebrations involving the first day of spring.  From 14th to 16th century much of the Western world celebrated the new year either with a party that lasted from March 25 to April 1  or on the resurrection of Jesus Christ, Easter. 

The date for Easter varies from year to year. Using the "Julian Calendar," Easter normally occurred around the first part of the month in April, the beginning of the season, Spring - as marked by the "vernal equinox." In Western astrology, the Tropical Zodiac still begins its yearly cycle in the Zodiac sign of Aries. 

In 1582 A.D., Pope Gregory XIII introduced what is now called the "Gregorian Calendar". The beginning of the new year was changed to more closely align the celebration of the new year with the birth of Jesus Christ. Ten days were deleted from the calendar, so that October 4, 1582 was followed by October 15, 1582. The vernal equinox, the first day of Spring, of 1583, and all subsequent years, occurred on or about March 21. 

The most common belief is that the observance of April Fool's Day began in France after the adoption of the reform calendar by Charles IX in 1564. When New Year's Day was changed to January 1. People who still celebrated New Year's Day on April 1 were the 'butt' of many jokes. They were called "Poisson d'Avril" (April Fish) because at that time of year the sun was in the zodiac sign of Pisces, the fish. In France it became customary to play tricks on family and friends.  French children fool their friends by taping a paper fish to their friends' backs. When the "young fool" discovers this trick, the prankster yells "Poisson d’Avril!"

In England, tricks can be played only in the morning. If a trick is played on you, you are a "noodle". In Scotland you are called an "April Gowk" or cuckoo bird. It lasts for two days there. The second day in Scotland is called Taily Day and is dedicated to pranks involving the buttocks. The Scotts can be given credit for the "Kick Me" and the 'to be the butt of a joke' expression.

Pesce d'Aprile! or April Fool's in Italy is traditionally a day of practical jokes, pranks, and silliness. The origin of this custom is ancient and ambiguous, but one thing is certain: much buffoonery and hilarity will take place. In Portugal, April Fool's is celebrated on the Sunday and Monday before Lent. The traditional trick there is to throw flour at your friends. 

Americans play small tricks on friends and strangers alike on the first of April. One common trick on April Fool's Day is pointing down to a friend's shoe and saying, "Your shoelace is untied." If victim falls for the joke the prankster yells, "April Fool!" Most April Fool jokes are harmless pranks. 

Sometimes articles in print and on line magazines are written 'tongue in cheek' as an April Fool's prank. The news media sometimes gets involved. A British short film once shown on April Fool's Day was a fairly detailed documentary about "spaghetti farmers" and how they harvest their crop from the spaghetti trees. 

April Fool's Day is a "for-fun-only" observance in which silly harmless pranks are played on others. There are no gifts to buy or celebrations to gear up for.  It's a fun little holiday, on which you must remain on the alert or you may be the next 
April Fool!

The Rainbow Painter

Sandy Sandman

Lollipop Castle

The Lily

Purple

Lemondrops

Technicolor

Peter Pan

Rainfall

The Sandman Awaits