Shortly after the Kraken's Awakening, a great event that disrupted the whole of Terra, the Magistery Guild held a summit in Solace. People of all countries and races attended, and among other decisions, everyone agreed to dictate a new passage of time that while arbitrary, would be universal. Colloquially people began referring to time in terms of "years after the kraken's awakening" which over the course of a century eventually shortened to "After Awakening," and subsequently before the Kraken's Awakening, people began to measure as "years before the Kraken Awakened," which was eventually shortened as BK.
A large number of conflicting yearly counts caused by inaccurate measurement methods, cultural differences, and location-based observation disagreements, this summit led to eventual agreement of The Common Era, and herafter it became largely referred to as BCE and CE, Before the Common Era and Common Era.