Factors that contributed to the growth of European imperialism:
The need for natural resources that could support the industries that had developed in Europe.
A belief in the superiority of Western culture and religion.
Effects it had on the world:
It led to enormous political and ethnic conflict in Africa. Africa was effectively partitioned in order to belong to many European states. This led to borders not matching ethnic and cultural ties, which led to conflict when Africa achieved its independence.
It allowed Europe to profit enormously and achieve a high quality of life. This was particularly obvious in the case of England.