There is no concrete evidence or documents depicting the decline of the Great Zimbabwe civilization. The theories as to why the population declined include; lack or resources, lack or trade, or political unrest.

After the Black Death, gold, resources, and trade declined. Then, for an approximate century, Kilwa prospered in trade. In the early 1500s, Portuguese fleets attacked Kilwa and demanded payments. Shortly after this period, the Portuguese became the leaders of trade in East Africa, leading to the decline of Kilwa.

Demises Of Civilization