April Fools' Day, sometimes called All Fools' Day, is one of the most light-hearted days of the year. Some see it as a celebration related to the turn of the seasons, while others believe it stems from the adoption of a new calendar.
愚人節的英語是April Fools’ Day，也叫做All Fools’ Day。有些人相信愚人節是為了慶祝季節變更，有些人則相信這是因為年歷的變更才形成的節日。
Ancient cultures, including those of the Romans and Hindus, celebrated New Year's Day on or around April 1. It closely follows the vernal equinox (March 20th or March 21st.) In medieval times, much of Europe celebrated March 25, the Feast of Annunciation, as the beginning of the new year.
古代文化，比如古羅馬和印度文化，都在4月1日左右慶祝胡新年。這個日子和春分(3月20日或者21日)很靠近。在中世紀時期，歐洲大多數國家在3月25日慶祝“圣母領報”，這一天被看作是新年的第一天。
In 1582, Pope Gregory XIII ordered a new calendar (the Gregorian Calendar) to replace the old Julian Calendar. The new calendar called for New Year's Day to be celebrated Jan. According to a popular explanation, many people either refused to accept the new date, or did not learn about it, and continued to celebrate New Year's Day on April 1. Other people began to make fun of these traditionalists, sending them on "fool's errands" or trying to trick them into believing something false. Eventually, the practice spread throughout Europe.
1582年，羅馬教皇格利高里八世創立了羅馬紀年法，來代替凱撒制定的儒略歷。羅馬紀年法將1月1日定為新年。人們相信，當時有一些人拒絕接受新年歷，或者他們根本不知道新年歷，他們仍然在4月1日慶祝新年。另外一些人便開始嘲諷這些堅定的傳統主義者，愚弄他們，差遣他們，或者擾亂他們的知識。最終，這個習俗傳到了整個歐洲。
當然這一個起源也有解釋不通的地方，比如英國很晚才開始使用羅馬紀年法，不可能跟這個愚人節搭上關系。雖然沒有定論，但至少，我們知道了愚人節的英語和愚人節的含義。