Imperialism, as defined by the People of Human Geography, is "the creation and/or maintenance of an unequal economic, cultural, and territorial relationship, usually between states and often in the form of an empire, based on domination and subordination." Lewis Samuel Feuer identifies two major subtypes of imperialism; the first is "regressive imperialism" identified with pure conquest, unequivocal exploitation, extermination or reductions of undesired peoples, and settlement of desired peoples into those territories, an example being Nazi Germany. The second type identified by Feurer is "progressive imperialism" that is founded upon a cosmopolitan view of humanity, that promotes the spread of civilization to allegedly "backward" societies to elevate living standards and culture in conquered territories, and allowance of a conquered people to assimilate into the imperial society, examples being the Roman Empire and British Empire.
Imperialism always involves the massive export of capital to foreign countries for the purpose of exploiting and dominating both their labor forces and their markets. Imperialism, the highest stage of capitalism, represents the stage at which a country's consumers cannot buy all the products that have been produced, and additional markets must be sought after. The dominant feature of imperialism is the repatriation of invested capital.
The term as such primarily has been applied to Western political and economic dominance in the 19th and 20th centuries. Some writers, such as Edward Said, use the term more broadly to describe any system of domination and subordination organized with an imperial center and a periphery. According to the Marxist historian, Walter Rodney, imperialism meant capitalist expansion. It meant that European (and North American and Japanese) capitalists were forced by the internal logic of their competitive system to seek abroad in less developed countries opportunities to control raw material, to find markets, and to find profitable fields of investment.
It's generally accepted that modern day colonialism is an expression of imperialism and cannot exist without the latter. The extent to which "informal" imperialism with no formal colonies is properly described as such remains a controversial topic among historians.
Read more about Imperialism: Overview, Colonialism Vs Imperialism, Age of Imperialism, Germany, Tsarist and Soviet Russian Imperialism, United States As "the World's Policeman", Justification