Imperialism can be described as the act of ruling another nation by military forces or by acquiring political and economic control of other areas.
Events such as the industrial revolution gave rise to imperialism. The growth and advancements in the industry caused people to dominate more lands so that they could have more resources for making goods as well a better and expanded market for customers buying their products.
The clashes in the ideologies of the Muslims, Hindus, Africans etc also contributed to imperialism.