The Calendar used in ATiTD is based on one of the several Calendars that the historic Egyptians used. The Year is divided into 12 months of 30 days, with three seasons of four months each. The three seasons are Akhet, Peret and Shemu. The four months of each season are written with Roman numerals.
* Shemu II-21 is the 21st day of the second month of Shemu. * Peret IV-18 is the 18th day of the fourth month of Peret.
As Egyptian time runs about three times as fast as earthbound time, an Egyptian month lasts about 10 Earth days.
The current calendar was introduced in one of the early Ages of Egypt (Beta 3) following a petition to the Pharaoh. The petition was organized by Aura, leader of the Sacred Rites guild. Sacred Rites was a guild devoted to the Worship Discipline, and to the belief that Egypt was the one real world, and the much talked about “Otherworld” an illusionary dreamworld. Hence the need for a true Egyptian calendar, rather than making do with the calendar of another, imaginary, world.
The calendar does tie back to the historic Egypt of the everyday world though. The three seasons tied to significant seasons in the year of Ancient Egypt. Akhet means inundation, when the Nile flooded the land for four months. Peret means emergence or growth, and Shemu low-water and harvest. Twelve months of thirty days is of course only a 360 day year, so five days of feasting and ritual were added to the end of the year. This feature wasn’t included in the ATiTD version of the calendar, due to the small size of the petitions in Aura’s day. Perhaps someone would like to correct that? Five days of feasting once a year sounds pretty good.
Even with the feast days, the calendar still doesn’t fit the actual length of the year. This official calendar was only accurate once every 1300 years or so. That didn’t seem to bother the Egyptians too much. They developed another calendar based on astronomical events to guide such activities as planting crops. The “civil” calendar denoted “virtual” seasons quite unconnected to the original Real Life events. So it seems well fitted to the Egypt of ATiTD.