Han dynasty

Dynasty of ancient China that came to power in 206 BC and ruled until AD 220 (with a brief interruption in AD 9-23, when the usurper Wang Mang seized power). Before AD 9 the dynasty was based at Chang'an and is sometimes known as the Western or Former Han; in the period after the capital was moved to Luoyang in 23, it is known as the Eastern or Later Han. Established by Gaozu, the dynasty introduced many of the traditional forms of Chinese imperial rule, including the centralized education system and bureaucracy.