The Wei dynasty fell in 534. It was succeeded by a series of rival regimes until nobleman Yang Jian (d 604) seized all before him to establish the Sui dynasty (581 -618). While the Sui was a short-lived dynasty, its accom- plishments were many. Yang Jian's great achievement was to bring the south back within the pale of a northern-based empire.

Yang Jian's son, Sui Yangdi, has gone down in history as an unsavoury character who had more time for wine and women than for politics; the dynasty went into rapid decline under his rule. Nevertheless, he did contribute greatly to the unification of south and north through the construction of the Grand Canal. The canal combined earlier canals and linked the lower Yangzi River valley to Chang'an via the Yellow River(Huang He). When Beijing became capital of the Yuan dynasty, it was re-routed and extended northward, and remained the empire's most important communication route between south and north until the late 19th century.