Imperialism is the practice of a nation extending its influence, taking over other countries, whether by colonization, or use of military force. Imperialism traces back to ancient Chinese history and extends up to and including World War I. Three periods in particular were the most fruitful for imperialism; between the 15th and 18th centuries, between the 19th century and World War I, and between the 1930s and 1940s, countries across the world began adopting imperialistic policies. To explore this concept, consider the following imperialism definition.

Definition of Imperialism


  1. The practice of a strong country exerting its influence over a weaker country to the extent that it dominates the weaker country’s economics, politics, and culture.


1855-1860       Latin    imperialis (of the empire or emperor)

What is Imperialism

Imperialism is characterized by a big or strong country taking over a smaller, weaker country; making that weaker country its own, including everything from land, to culture, and politics. Imperialism is all about the power that the larger nation has over the smaller nation, which enables it to take over through the use of military force or negotiation. The word “imperialism” grew in popular use in Europe during the 1870s, and the word itself was often associated with a negative meaning, as it was commonly used to describe the politics and tactics of Napoleon III.

History of Imperialism

The history of imperialism finds its roots in China, as well as in the ancient cultures of western Asia and the Mediterranean, by way of a series of empires. The Persian Empire, for example, replaced that of the Assyrians, around the 6th to the 4th centuries B.C.E., and was considerably superior in terms of how they treated their subjects, as the Assyrians’ rule was more tyrannical in comparison to the liberalism of the Persian Empire.

From here the history of imperialism moves on to Ancient Greece, where imperialism reached its peak under Alexander the Great’s rule from 356 to 323 B.C.E., when the eastern Mediterranean fused with western Asia. Alexander’s goal was to create a cosmopolis, in which everyone in the world would live together peacefully and equally. This dream remained out of reach for Alexander, though it partly came to be when the Roman Empire emerged, embracing all of the peoples from Britain to Egypt.

Unfortunately, the idea of an empire being a unification of sorts was not revisited until Rome fell. This is when the history of imperialism changed course and became more disruptive than unifying. The nations who struggled to find their footing after the fall of the Roman Empire pursued separate imperialist policies from those of Asia, rather than attempting to join forces with one another.

Periods of Imperialism

Three periods in the history of imperialism experienced far more empire-creation than any other points in time. The first occurred between the 15th and middle of the 18th centuries, when England, France, Portugal, Spain, and the Netherlands founded empires in India, the East Indies, and America.

The second period occurred between the middle of the 19th century and the years during World War I, when Russia, Japan, Italy, Germany, and the U.S. all turned to imperialistic policies. Finally, the third period began when Japan attacked China in 1931, ushering in a new period of imperialism that took place during the 1930s and 1940s, and included Japan, Nazi Germany, the Soviet Union, and Fascist Italy.

Modern Examples of Imperialism

In 1917, Russian politician Vladimir Lenin wrote Imperialism, the Highest Stage of Capitalism in response to Karl Marx’s Das Kapital (1867). In Lenin’s essay, he went on to discuss how financial profits played a role in helping imperialist colonialism generate profits, so as to ensure the greatest amount of revenues possible for capitalist development.

The post-World War I publications of Imperialism, the Highest Stage of Capitalism illustrated how the 1918 Russo-German Treaty of Brest-Litovsk, and the 1919 Allied-German Treaty of Versailles, were both evidence that imperialism and control were the motivation for the war, not patriotism.


Cartography was actually very important to imperialism, which is understandable when considering how maps are more of a political representation of the world, than the realistic geographical tool they are usually believed to be. This is despite the seemingly innocent definition of cartography being that of “making maps.” Nineteenth century maps include a lot of blank spaces, which left in order to motivate imperial and colonial powers both to find out information about these blank areas, and to fill in the maps with the lands they discovered by invading them.

Of course, maps have been greatly improved over the years since the days of imperialism, but proof still exists that the cartography process is particularly biased in favor of European experiences and points of view. For instance, while 19th century explorers would ask Africans to create maps for them of the areas with which they were unfamiliar, those maps were not printed in Europe, unless Europeans were able to review and verify them first, despite the fact that these maps were often highly praised for their levels of accuracy.

Imperialism vs. Colonialism

The terms “imperialism” and “colonialism” are often used interchangeably; however, scholars argue that there are more than a few differences that separate the two. According to the late Edward Said, a professor from Columbia University, imperialism is more like dominating and ruling a specific region and making everything about that region your own, while colonialism is more like finding a place for an already established settlement on new land and continuing to respect the laws of that land.

U.S. Imperialism

U.S. imperialism is the United States’ expansion into other countries through the use of economic, military, and cultural influences. Despite early opposition to the practice, U.S. imperialism did have supporters, as was evidenced by Thomas Jefferson saying, during the 1790s, that he was waiting for the U.S. to become advanced enough to take over the Spanish Empire when it eventually fell.

The idea of an American empire really started to gain traction during James K. Polk’s presidency, as he led the U.S. into the Mexican-American War (1846). The U.S. also eventually annexed California and additional territories in the West by way of the Treaty of Guadalupe Hidalgo and the Gadsden purchase.

U.S. imperialism continued into the late 19th century, when the U.S. sought out foreign territories like Hawaii, and Latin America. Both the Teller and Platt Amendments were devised to permit the U.S. to involve itself with both territories, should proof be established that their governments were too unstable to successfully run themselves. U.S. imperialism hit its peak in the years following World War II, after Germany and Austria surrendered, followed by the surrenders of Japan and Korea in 1945.

The Anti-Imperialist League

Americans who were against imperialism decided to take matters into their own hands in 1898. The creation of the Anti-Imperialist League was intended to protect the United States’ annexation of the Philippines and Cuba. The League was not alone in their plight, as they would soon find out, as the Teller and Platt Amendments were created to place a limit on potential.

The year following the creation of the League, war broke out in the Philippines, which U.S. imperialism resulted in United States leaders denouncing their country’s occupation of the country. They also attributed the numerous Filipino deaths that resulted from the war to the United States’ involvement. This is an example of U.S. imperialism that went unexpectedly south.

Teller Amendment

The Teller Amendment, enacted on April 20, 1898, was an amendment to a joint resolution created by Congress, in reply to President William McKinley’s War Message, and it restricted the United States military’s presence in Cuba by limiting them to helping Cuba gain its independence. Once that goal was met, all American troops would be withdrawn from the country. The U.S. was not permitted to annex Cuba, and was directed to leave control of the country in its inhabitants’ hands.

The Teller Amendment was named for Republican Senator Henry M. Teller from Colorado, who proposed the amendment to assure Cuba that the U.S. would not attempt to establish a permanent residence in, or control of their country after their recent separation from Spain.

Platt Amendment

In cooperation with the Teller Amendment, the Platt Amendment was passed on March 2, 1901, specifying seven conditions for the United States military’s withdrawal from Cuba. It also included an eighth condition wherein Cuba would sign a treaty accepting the seven conditions. The Platt Amendment was named for Senator Orville H. Platt, who introduced the proposal to Congress on February 25, 1901.

On December 25 of that year, Cuba amended its constitution to include the terms of the Platt Amendment, and on May 22, 1903, Cuba entered the Cuban-American Treaty of Relations. This treaty actually permitted the U.S. to be involved in Cuban matters, and leased Cuban land to establish American naval bases.

Imperialism Example

The most notable examples of imperialism in the U.S. are found the Insular Cases. These cases were given the term “Insular” because they concerned territories that administered by the War Department’s Bureau of Insular Affairs.

The Insular Cases

A series of decisions rendered by the U.S. Supreme Court in 1901, addressed the issue of American imperialism, as the nation gained territories during the Spanish-American War, following the signing of the Treaty of Paris in 1898. Concerns were raised about how these new territories should be governed, since no direction had been given in the Constitution. The Court ruled that, just because a parcel of land is under the control of the United States, does not mean the people of that land are entitled to the same constitutional rights Americans enjoy.

So those living in unincorporated territories, such as Puerto Rico, may be denied certain constitutional rights (like the ability to remain with the United States should a de-annexation occur), even if they are technically considered to be U.S. citizens.

Although, in this example of imperialism there are six Supreme Court cases referred to as “the Insular Cases,” some law experts consider more cases to be part of that group, expanding the date range through 1979. When considered in this timeframe, there are nine Insular Cases. Interestingly, six of the nine Insular Cases only include Puerto Rico as a territory.

Related Legal Terms and Issues

  • Annex – To incorporate territory into the domain of a country, state, or city.
  • Eurocentrism – Having a focus on European history or culture, to the exclusion of a broader world view.
  • Treaty – A formal agreement between two or more countries.