The Great Zimbabwe was the first great empire to arise in Southern Africa. The empire was ruled by a hereditary monarchy of elites. This means the power stayed with on family. The highest point of the empire was mid fifteenth century. The "parliament" was comprised of members of families close to the monarch. Separate regions of the empire were ruled by regional governors appointed by the king. In the center of the Great Zimbabwe ruins lies "the great enclosure" which housed towers and buildings controlled by the "mambos." Outside of the monarch only one other group of people held any power and they were known as "mambos". They were chiefs who persisted and eventually gained control over smaller Shona groups. The mambos worked out deals with regional governors by giving them cattle and livestock. The mambos also recognition by officials and the officials were not willing to do this so they instead would pay fees to get the mambos from pestering them. Experts on ancient African culture and politics believe that the Zimbabwe were a highly sophisticated society with all the parts needed to be a functional society. The decline of the empire is not attributed to political system failure whish is a change from most societies. The decline is credited to over-population and natural causes such as draught and the lessening supply of gold.