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The Editors of Encyclopaedia Britannica Below is the article summary. For the full article, see imperialism.imperialism, State policy, practice, or advocacy of extending power and dominion, especially by direct territorial acquisition or by gaining political and economic control of other areas.
In ancient times, rulers in China, western Asia, and the Mediterranean extended their power through imperialism. Between the 15th century and the middle of the 18th, England, France, the Netherlands, Portugal, and Spain built empires in the Americas, India, and the East Indies.
Russia, Italy, Germany, the United States, and Japan became imperial powers in the period from the middle of the 19th century to World War I. The imperial designs of Japan, fascist Italy, and Nazi Germany in the 1930s culminated in the outbreak of World War II. After the war, the Soviet Union consolidated its military and political control of the states of eastern Europe. From the early 20th century the U.S. was accused of imperialism for intervening in the affairs of developing countries in order to protect the interests of U.S.-based international corporations.
Because imperialism always involves the use of power, it is widely considered morally objectionable. Economists and political theorists have debated whether imperialism benefits the states that practice it and whether such benefits or other reasons justify a state in pursuing imperialist polices. Some theorists, such as Niccolò Machiavelli, have argued that imperialism is the justified result of the natural struggle for survival. Others have asserted that imperialism is necessary in order to ensure national security. A third justification, offered only infrequently after World War II, is that it is a means of liberating peoples from tyrannical rule or improving their standard of living.
Almoravids, confederation of Berber tribes—Lamtūnah, Gudālah, Massūfah—of the Ṣanhājah clan, whose religious zeal and military enterprise built an empire in northwestern Africa and Muslim Spain in the 11th and 12th centuries. These Saharan Berbers were inspired to improve their knowledge of Islamic
Delian League, confederacy of ancient Greek states under the leadership of Athens, with headquarters at Delos, founded in 478 bce during the Greco-Persian wars. The original organization of the league, as sketched by Thucydides, indicates that all Greeks were invited to join to protect themselves
Monroe Doctrine, (December 2, 1823), cornerstone of U.S. foreign policy enunciated by Pres. James Monroe in his annual message to Congress. Declaring that the Old World and New World had different systems and must remain distinct spheres, Monroe made four basic points: (1) the United States would
British Empire, a worldwide system of dependencies—colonies, protectorates, and other territories—that over a span of some three centuries was brought under the sovereignty of the crown of Great Britain and the administration of the British government. The policy of granting or recognizing
