China: Sui dynasty (AD 589-618)
During the Sui dynasty, northern and southern China were reunified after centuries of division, and political, educational and economic foundations were laid on which the great Tang and later dynasties were to build. Yang Jian, the Northern Zhou general who established himself as the Sui emperor Wendi, improved many aspects of internal administration. He also instigated a program of public works which included the complex canal system that links the Yellow, Huai and Yangzi Rivers.
An exam system was implemented by the second emperor, Yangdi (AD 568-618), which was based on the study of Confucian classics. This was designed to attract scholars from the southern and north-eastern élites into the bureaucracy. Yangdi was extrememly ambitious and energetic, pursuing an active foreign policy and extending the trade routes into Central Asia and the West.
The failure of military campaigns in Korea in 612 and 614 and against the Turks however, financially ruined the dynasty. Yangdi fled south, leaving the north to be run by various rebel regimes. Floods and peasant uprisings ensued, adding to the disastrous events of the previous few years. When Yangdi was eventually murdered by members of his entourage, a general who had been responsible for defending China against the nomads, Li Yuan (known posthumously as Emperor Gaozu), rebelled, and marched on the captial Chang'an, where he founded the Tang dynasty in 618.