The calendar counts years relative to the Exodus of the Gods, an event that took place 1072 years prior to the beginning of the game. Years Before the Exodus (BE) and After the Exodus (AE) increase the further the date is from the Exodus.
For an overview of key dates from the Mouvelian Calendar, see History of Tyria.
Calendar does not affect gameplay. Except for special real-world celebrations within certain towns, the "current date" within the gameworld is usually only specified to the year, not the month nor the day, however the final mission of Guild Wars Prophecies is stated to take place "long into the Season of the Scion".
The year in the Mouvelian Calendar is made of 360 days divided into 4 seasons, dedicated to the 4 elements:
|Name||Season of the ...||Days||Element|
Note that, although the Mouvelian Calendar and Dynastic Reckoning use the same names for the seasons, the elements associated with the last two seasons differs in the two calendars, and the Mouvelian Calendar does not explicitly associate any of the seasons with specific gods.