The first calendar known to use a year of 365 days, is introduced in Egypt, with an year divided into 12 months of 30 days and 5 or 6 days added at the end


Ancient Egypt


Very important (8)




The Egyptian civil calendar was introduced later, presumably for more-precise administrative and accounting purposes. It consisted of 365 days organized into 12 months of 30 days each, with an additional five epagomenal days (days occurring outside the ordinary temporal construct) grouped at the end of the year. There was apparently no attempt to introduce a leap-year day to compensate for the slippage of one day every four years; as a result, the civil calendar slowly rotated through the seasons, making a complete cycle through the solar calendar after 1,460 years (referred to as a Sothic cycle).

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