The Black Plague is believed to be caused by rats and the bad sanitation and the water they drank.
Three effects Africa encountered because of European Imperialism were shortages of natural resources, death of Africans from European diseases, and increase of wars and revolutions. Europeans exported raw materials, such as diamonds, gold, and timber. However, the constant mining and deforestation caused a lack of resources for Africans and hurt their economies. With Europeans colonists coming into the African nations, European diseases like small pox were introduced and killed large numbers of the population. Europeans colonizing Africa destroyed cultures and their local politics. This caused uprisings in many cultures, and civil wars erupted within cultures. Furthermore, revolutions led by African natives occurred against European colonists.
