The civil calendar in Ancient Egypt, used to record dates on official documents and monuments, was divided into three seasons, with each season consisting of four 30-day months, for a total of 360 days. At the end of each year, five additional days, called “epagomenal” days by Egyptologists, were added, bringing the total length of the year to 365 days. The actual length of the year is about 365.25 days, meaning that the calendar gradually fell out of step with the seasons, but the Egyptians seem to have had no problem with the fact that this happened!
The three seasons were based around the agricultural year, which traditionally started with the annual inundation (flooding) of the Nile which occurred around mid July. The first season was called Akhet (“inundation”), the second Peret (“emergence”) and the third Shemu (“harvest”).
Each month was divided into three 10-day weeks, called decans. There is evidence from the village of the royal craftsmen, Deir el-Medina, to suggest that, during the 19th and 20th dynasties at least, the last two days of each decan were a “weekend”, during which the craftsmen did not have to work.
Dates were written as the number of the month within the season from 1 to 4 (with the number 1 commonly being replaced by “first”), then the name of the season, and finally the number of the day within the month, from 1 to 30 (with the word “last” commonly being used instead of 30). Thus 3 Akhet 12 means the 12th day of the third month of the season of Akhet, and 1 Peret last means the last day of the first month of Peret.
The five epagomenal days occurred at the end of each year, immediately following 4 Shemu 30, and were called “those over the year” by the Egyptians. They were festival days, and were celebrated as the birthdays of particular gods, as follows:
- Day 1: The birth of Osiris
- Day 2: The birth of Horus
- Day 3: The birth of Set
- Day 4: The birth of Isis
- Day 5: The birth of Nephthys
The day after epagomenal day 5 was the first day of the new year, 1 Akhet 1, which was called “the opening of the year” and celebrated as the birth of Re. In writing, the epagomenal days could either be referred to by number (as those over the year 3 for the third epagomenal day), or by name (as the birth of Set).
The year was recorded in terms of “regnal years”, or the number of years the current king had been on the throne, so a complete record of a date would be in the form Year 6, first Shemu 18, meaning the 18th day of the first month of the season of Shemu, in the 6th year of the king’s reign.
To complicate matters, an entirely different calendar was used for the dating of religious festivals. This was a lunar calendar, in which each month began on the morning on which the waning crescent moon could no longer be seen, and days in the month were counted from this occurrence. The months in the lunar calendar were referred to by name rather than number, with different names for the months being used at different periods of Egyptian history, and perhaps also different names being used in different parts of the country. The names of the lunar months used in Thebes during the New Kingdom are still used today in the religious calendar of the Coptic Church.
As I noted at the beginning of this article, the Egyptian calendar did not have leap years, and so the civil calendar gradually drifted with respect to the seasons, falling behind the seasons by about one day every four years. So the start of the year, 1 Akhet 1, although it nominally referred to the start of the inundation of the Nile, actually occurred at completely different times of the year at different periods in Egyptian history, taking 1461 years to go through a complete cycle. Thus there is no straightforward way to convert dates in the Egyptian civil calendar to modern calendar dates.