What economic, political, and social conditions encouraged the growth of imperialism in Africa and Asia?

Before Europeans overtook Africa, tribes often fought with each other. After that, they had no other choice but to deal with it. The Africans were not able to defend their territory because of the outdated technology. Europeans used all the natural goods in Africa, enslaved the locals and forced them to work. The very same case scenario can be viewed in British invasion of India. British-Indian economic ties were in neo-mercantilist level. Using India's natural resources, such as wool and cotton, Britain were doing trade with China. Britain's economic interests worsened with the Opium Wars which created lawlessness and economic, political and military domination of Europeans over China.

One of the more important conditions one needs to consider with Africa and Asia in parts where imperialism was being spread was that they has politically unstable countries, were economically depriviliged, and the social conditions were not good. When imperialist countries came to exert influence, while it first seemed everyone would benefit from this relationship, it soon became obvious that this was not the case.