The Zhou created the Mandate of Heaven: the idea that there could be only one legitimate ruler of China at a time, and that this ruler had the blessing of the gods. They used this Mandate to justify their overthrow of the Shang, and their subsequent rule.
The mandate of heaven was the celestial document that the Chinese emperors derived their power from. It gave the emperors full power but allowed for the Chinese people to revolt and overthrow the dynasty if to many natural disasters/bad events happened under his rule.
