Mandate Of Heaven Wiki
https://en.wikipedia.org/wiki/Mandate_of_Heaven
The Mandate of Heaven is a Chinese political philosophy that was used in ancient and imperial China to legitimize the rule of the King or Emperor of China.
If a ruler was overthrown, this was interpreted as an indication that the ruler was unworthy and had lost the mandate. It was also a common belief that natural disasters such as famine and flood were divine retributions bearing signs of Heaven's displeasure with the ruler, so there would often be revolts following major disasters as the people saw these calamities as signs that the Mandate of Heaven had been withdrawn.