The Sui dynasty was a Chinese imperial dynasty that ruled from 581 to 618 AD. The re-unification of China proper under the Sui brought the Northern and Southern dynasties era to a close, ending a prolonged period of political division since the War of the Eight Princes. The Sui endeavoured to rebuild the state, re-establishing and reforming many imperial institutions; in so doing, the Sui laid much of the foundation for the subsequent Tang dynasty, which after toppling the Sui would ultimately preside over a new golden age in Chinese history. Often compared to the Qin dynasty (221–206 BC), the Sui likewise unified China after a prolonged period of division, undertook wide-ranging reforms and construction projects to consolidate state power, and collapsed after a brief period.