Coptic calendar

This calendar is based on the ancient Egyptian calendar. This calendar contained only 365 days each year, year after year, so that the date relative to the seasons shifted about one day every four years. To avoid the "creep" of the latter around the seasons, a reform of the ancient Egyptian calendar was introduced at the time of Ptolemy III (Decree of Canopus, in 238 BC) which consisted of adding an extra day every fourth year. However, this reform was opposed by the Egyptian priests, and the reform was not adopted until the Roman Emperor Augustus decreed that Egypt must adopt the system as its official calendar. To distinguish it from the Ancient Egyptian calendar, which remained in use by some astronomers until medieval times, this reformed calendar is known as the Coptic or Alexandrian calendar and its epoch (first day of first year) equates to 29 August 284AD. The neighbouring Ethiopian calendar is very similar to the Coptic calendar, except that it has a different epoch (29 August, 8AD) and different names for the days of the week and months of the year. == Coptic year ==

The Coptic year is the extension of the ancient Egyptian civil year, retaining its subdivision into the three seasons, four months each. The three seasons are commemorated by special prayers in the Coptic Liturgy. This calendar is still in use all over Egypt by farmers to keep track of the various agricultural seasons. The Coptic calendar has 13 months, 12 of 30 days each and one at the end of the year of five days (six days in leap years). The Coptic Leap Year follows the same rules as the Julian Calendar so that the extra month always has six days in the year before a Julian Leap Year. The year starts on the Feast of Neyrouz, the first day of the month of Thout, the first month of the Egyptian year. For 1900 to 2099 it coincides with the Gregorian Calendar's 11 September, or 12 September before a leap year. For any year, it coincides with the Julian Calendar's 29 August, or 30 August before a leap year. Coptic years are counted from 284 AD, the year Diocletian became Roman Emperor, whose reign was marked by tortures and mass executions of Christians, especially in Egypt.) == Coptic months ==

The following table refers to dates for Coptic years not containing 29 February. Such years are preceded by a Coptic leap day at the end of the preceding year. This causes dates to move one day later in the Julian and Gregorian Calendars from the Coptic New Year's Day until the leap day of the Julian or Gregorian Calendar respectively. == Further reading ==