Era beginning/end
Referred to as "The End" by scholars.
Many books predate "The End", however no one seems to know how long the era truly lasted for. Ancient texts describe The End as a cataclysmic end of the world. Many texts point to a prophecy of 5 chosen individuals who would stop the event from happening. It is not clear what happened, as the texts do not explain The End, nor does anyone have any memory of the era. Life seemed to simply start again. All events before are described as "Before the End" (BE) and after as "After the End" (AE).