April 1st 2001 in Denmark, regarding Copenhagen's new subway

Like other holidays discussed on EverythingIsHistory.com, the origins of April Fools’ Day is pretty much unknown. One legend posits that Noah released the Raven during the Great Flood on April 1st (the Raven did not return). Of course, there are obvious reasons why that explanation about April Fools’ Day is nothing more than a legend. Other given explanations have included Greeks, Romans, Pagans, etc., and of course these are just legends, also. Here at EiH, though, I deal in fact, so here’s the raw intelligence and most logical explanation about the origins of April Fools’ Day. In 1582, Europe transitioned from the Julian calendar to the Gregorian calendar, which changed New Year’s Day from March 25 to January 1. Those who continued to celebrate the culmination of New Year Week on April 1 were called April Fools. A related explanation for April Fools’ Day is that people are fooled by the sudden changes in weather associated with the changing of the seasons.

Common April Fools’ Day Observances
There are variations between countries in the celebration of April Fools’ Day, but all have in common an excuse to make someone play the fool. In France, for example, the fooled person is called poisson d’avril (“April fish”), perhaps in reference to a young fish and hence to one that is easily caught; it is common for French children to pin a paper fish to the backs of unsuspecting friends. In Scotland the day is Gowkie Day, for the gowk, or cuckoo, a symbol of the fool and the cuckold, which suggests that it may have been associated at one time with sexual license; on the following day signs reading “kick me” are pinned to friends’ backs. In many countries newspapers and the other media participate—for example, with false headlines or news stories. Compliments of Encyclopedia Brittanica.

Notable Hoaxes

• In 1985, Sports Illustrated published an article about a baseball prospect for the New York Mets named Sidd Finch who could throw a baseball 168 mph. According to the article’s author, George Plimpton, Mr. Finch had no minor league experience and was actually discovered in a Tibetan monastery. Although the record for a major league pitch at the time was only 100.9 mph, Mets fans wrote SI in droves trying to get more info about their newest prospect.
• In the 1950s, a Dutch News Program reported that the leaning Tower of Pisa had fallen over *tee hee*.
• In 1957, the BBC ran a documentary about Swiss Spaghetti Trees:

Corporate April Fools’ Day Hoaxes

• Every year Google releases a fake product or service in honor of April Fools’ Day. My personal favorite of theirs is the Google TiSP; Toilet Internet Service Provider. For more Google hijinx check out http://en.wikipedia.org/wiki/Google%27s_hoaxes
  UPDATE: Google’s prank this year: Gmail Autopilot!
• NPR runs an extensive April Fools’ Day hoax annually. The stories generally begin reasonably enough but get more and more ludicrous. In 2003, All Things Considered published a story called “Post Office Calls for Portable ‘Vanity’ Zip Codes”.

April Fools’ Day Non-hoaxes
Sometimes real news happens on April Fools’ Day and it is automatically assumed to be a prank, sometimes with disastrous consequences. Here’s a short list of those occurrences:

• The April 1, 1946 Aleutian Island earthquake tsunami that killed 165 people in Hawaii and Alaska resulted in the creation of the Pacific Tsunami Warning Centre. The tsunami in question is known in Hawaii as the “April Fools’ Day Tsunami” due to people drowning because of the assumptions that the warnings were an April Fools’ prank.
• The 2005 death of comedian Mitch Hedberg was originally dismissed as an April Fools’ joke. The comedian’s March 29, 2005 death was announced on March 31, but many newspapers didn’t carry the story until April 1, 2005.
• Google’s April 2004 launch of their email service GMail was widely believed to be a prank.
• On April 1, 1984, singer Marvin Gaye was shot and killed by his father. Originally, people assumed that it was a fake news story, especially considering the bizarre aspect of the father being the murderer.

For more insight into the origins of human traditions, check out Black Cats and April Fools: Origins of Old Wives Tales and Superstitions in Our Daily Lives