Imperialism is the policy or action by which one country controls another country or territory. Control is achieved by military means to gain economic and political advantages. An imperialist government may wish to gain new markets for its exports, plus sources of inexpensive labor and raw materials. A far-flung empire may satisfy a nation's desire for military advantage or recognition as a world power.
Imperialism has been the driving force behind most wars, territorial expansion, and cultural exchange.
The western part of the empire collapsed in the A.D. 400's, but the eastern section, called the Byzantine Empire, survived until 1453. The western part of the Roman Empire was revived in name only as the Holy Roman Empire. The Mongols, built the largest land empire in history in the 1200's. It extended from Southeast Asia to eastern Europe. Spain established colonies in what is now Latin America and the southern United States. By the early 1700's, the British, French, and Dutch had colonized much of eastern North America. The Dutch gained control of the Indonesia area and the British began their rule of India. The late 1800's are often called the Age of Imperialism. During this period, France, Germany, Great Britain, Italy, divided up nearly all of Africa. During the 1930's, Germany, under the rule of Adolf Hitler, began a program of expansion in Europe.
Many theories attempt to explain the motives for imperialism. One of the best-known theories focuses on economic profit as the chief reason for a nation to seek foreign territories. Industrialized nations can produce more manufactured goods than their people need or can afford to buy. Colonies may serve as markets for these unsold products. They also may provide cheap land and valuable natural resources. However, because of imperialism many colonies were not economically profitable. Military strategy is another important motive for imperialistic activity.