CER abbreviation for: Celtic Empire Reckoning
The starting point for this calender is the peak of the Celtic Empire. The Great Druid Olmanx declared that the empire would last for a thousand years after seeing how far the reach of the Celtic World was at this point.
The downfall of the Empire was precipitated in 371 CER when the city of Wolfspack on the western side of the Great Mountains declared independence. Shortly thereafter the Empire was torn asunder through several wars.