Some writers suggest that April Fools’ originated because in the Middle Ages, New Year’s Day was celebrated on March 25 in most European towns,^[9] with a holiday that in some areas of France, specifically, ended on April 1,^[10][11] and those who celebrated New Year’s Eve on January 1 made fun of those who celebrated on other dates by the invention of April Fools’ Day.^[10] The use of January 1 as New Year’s Day became common in France only in the mid-16th century,^[7] and the date was not adopted officially until 1564, by the Edict of Roussillon.

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