In 221 BCE, King Ying Zheng of Qin conquered the rival warring states and established the Qin empire as Qin Shi Huangdi (The First August Emperor ... Han Dynasty. During four centuries of Han rule ...

when at the centre the emperor was under severe threat and, at the edges of the Empire, he was struggling to keep control. The Han had extended Chinese power as far south as Vietnam, west to the ...