Nobody is sure how April Fool’s Day got started, but the most common theory is the changing of the calendar from the Julian to the Gregorian in France in 1564. The Julian calendar, based on lunar cycles, celebrated the New Year in April. The Gregorian calendar, based on the sun, celebrated the New Year on January 1st. Not everyone was pleased about the new calendar, and some refused to recognize it. These individuals became known as April Fools when they insisted on celebrating the New Year in April.
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