The title Son of Heaven (Tianzi) expressed the ruling ideology of imperial China: that the emperor governed by the Mandate of Heaven (Tianming), a conditional divine sanction granted to a just ruler and withdrawn from an unjust one, made visible through prosperity or, conversely, through famine, natural disaster and popular rebellion. The concept was articulated by the Zhou dynasty around the eleventh century BCE to justify its conquest of the preceding Shang dynasty, whose last king Zhou tradition portrayed as tyrannical and therefore rightly overthrown, a doctrine that simultaneously legitimated the new dynasty and set a standard by which future rulers, including the Zhou's own eventual successors, could likewise be judged and replaced.
Unlike the unconditional divine right claimed by some other monarchies, the Mandate of Heaven was explicitly revocable, giving Chinese political thought a built-in justification for dynastic change that later Confucian scholars developed into an elaborate theory of the dynastic cycle: founding, consolidation, decline through misgovernment, and eventual collapse and replacement. Each new dynasty, from the Han through the Tang, Song, Ming and Qing, claimed the Mandate afresh, and imperial rituals, chief among them the emperor's own sacrifices to Heaven at sites such as Beijing's Temple of Heaven, performed and reaffirmed this claim publicly.