Name several things that can lead to a mandate of heaven

According to this belief, heaven bestows its mandate to a just ruler, the Son of Heaven. The Mandate of Heaven depends on whether an emperor is sufficiently virtuous to rule; if he does not fulfill his obligations as emperor, then he loses the Mandate and thus the right to be emperor. The Mandate of Heaven would then transfer to those who would rule best. The fact that a ruler was overthrown was taken by itself as an indication that the ruler had lost the Mandate of Heaven. In addition, it was also common belief that natural disasters such as famine and flood were other signs of heaven’s displeasure with the current ruler, so there would often be revolts following major environmental events as citizens saw these as signs of heaven's displeasure