What empires do you know of that, like the Eastern Roman Empire, withdrew from their former core territory and reestablished themselves in a new area?
- The Umayyad Caliphate fell in the Middle East, but established the Emirate of Cordoba, and later the Caliphate of Cordoba.
- The Seljuk Empire disintegrated in the east, but the Seljuk Sultanate of Rum survived in Anatolia
- The Golden Horde survived beyond the collapse of the Yuan Dynasty
- The Timurids re-established themselves in India as the Mughal Empire