The Tang Dynasty grew out of the turmoil left by the Sui. Initially, the Tang had to fight other contenders for the throne and it was not until AD628 that the last rebellion against it was crushed. The Tang conquest was marked by brilliant military leadership. The rules of civil government were established early on and remained in place throughout the dynasty. The Tang also cultivated contacts with tribes all over Asia and foreign powers such as the Byzantium and Iranian. The introduction of Buddhism into China, among other influences, was the result.
In the mid-600s, drama at the court saw in an empress who would stand no challenge to her influence. Oddly enough, a rebellion by the Tang royal family rose up against what it saw as undue pretension on the empress' behalf. A purge followed and many were killed. In AD690, the Empress Wu installed herself as supreme ruler and became the only female to ascend the throne in Chinese history. When she died, power reverted to the Tang royal family. A period of corruption followed until AD712 when the Tang Dynasty entered its most glorious period. Cultural activities flourished, corruption ended and successful defence measures were introduced. But tension was not far away. As the aristocrats responsible for much of the reforms took power, the emperor gradually withdrew into study.
Rebellion in the north from AD750-763, which rose from a rivalry between two generals, left millions dead and millions more displaced further south. The center of the rebellion remained in [M 004 / Hebei] Province and this lasted well into the ninth century. In the eighth and ninth centuries, the south gained prominence as China's economic center. Along with this came social changes - the old aristocracy gave way to an educated class.
Various uprisings and natural disasters, such as the floods and droughts in the Yangtze Valley in the AD830s and the mutinies in the provincial armies deployed in the south, led to the downfall of the Tang Dynasty. China, by then, had been carved up into regions with their separate power bases.
