2.+The+overthrow+of+the+Sui+Dynasty

The incompetent emperor Yang of Sui (Yang Ying) is considered greatly responsible for the downfall of the Sui Dynasty. Yang of Sui ruled from 604 to 617 C.E before being seceded by his second son, the child emperor Gong of Sui. Duke Li Yuan of the Sui Dynasty used this new emperor as his 'puppet child emperor' until Yang of Sui was murdered by his General Yuwen Huaji (later to be known as Gaozu of Tang) and he seized the throne (June 18, 618 C.E).

Left: Emperor Yang of Sui, Middle: The influence of the Sui Dynasty, Right: Duke/Emperor Li Yuan