Nebulan Cataclysm

The Nebulan Cataclysm, also known as the Nebulan Civil War or the Viachet-Nashka'n War of Succession, was a 2,000 year long conflict fought between the warring Viachet and Nashka'n dynasties after the death of the last monarch of the Krion dynasty. The conflict led to the destruction of much of the Nebulan Empire's territory and the resetting of Nebulan advancement to the equivalent of Earth's Early Middle Ages.