Era of Princess Celestia

The "Era of Princess Celestia" defines the point in history from Princess Luna's banishment all the way until her redemption, nearly 1,000 years worth of history. It was proceeded by the much briefer "Era of Two Sisters" and suceeded by the even breafer "Era of Harmony". It is currently the longest defined period of history, outside of periods with unclear start and stop dates. Known for warfare, strife, rebuilding, education, high adventure and expansion, the era has left a mark on Equestria that will never go away.