The United States began as a confederation of thirteen former British colonies on the eastern seaboard of the Atlantic Ocean, with relatively little international influence. Over the next century the United States spread across the whole North American continent.

Early expansion

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Even before the United States was formed, there was an attempt to include the more northern British colonies in what became Canada into the territory controlled by the Continental Congress. These efforts continued in the War of 1812 and the ambition to have one federal nation in North America is known as Manifest Destiny. Historians such as William Appleman Williams argue that a major step on the road to imperialism was the conquest of the Native American peoples who inhabited North America. The American expansion westward had many similarities to European activities in Africa and the first arrivals of Europeans in the Americas.

The Louisiana Territory

The Louisiana Purchase, the 1803 transaction of the gigantic western Louisiana Territory from France (Napoleon Bonaparte) to the United States (Thomas Jefferson), is often considered the first major event in American expansion, although it is rarely cited as an act of imperialism.

After the Louisiana Purchase, Thomas Jefferson signed the Louisiana Government Bill, which denied the new United States territory the right to self-government. Instead, it was to be ruled by military officials under direct orders from the capital of the Nation. Since most of the population of the territory consisted of non-whites and Catholics, Jefferson felt that the government should suspend its right to self-government until enough white settlers moved west to command a majority. Modern-day critics of this choice point out the irony in the fact that Jefferson, who had decried British denial of American self rule in the Declaration of Independence, was now issuing the orders to deny self-rule in an American territory, issuing commands from half-way across the continent.

Texas Annexation

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The Texas Annexation of 1845 was the voluntary annexation of Republic of Texas by the United States of America as Texas, the 28th state, and additional land that later became major parts of the states of New Mexico and Colorado, where the headwaters of the Rio Grande exist in the Sangre de Cristo Mountains.

Mexican-American War

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The Mexican-American War from 1846 to 1848 is often viewed as motivated by American imperialism. In 1846,U.S. President James K. Polk sent soldiers to the disputed zone between Mexico and the newly annexed Texas in what most historians describe as a provocation for war. After war broke out, American forces quickly defeated those of Mexico, and in the Treaty of Guadalupe Hidalgo, Mexico ceded its claims on what is now almost the entire Southwest and California to the United States, in exchange for $15 million and the settlement of pending individual claims against Mexico valued at about $3 million.

Many aspects of the war and its aftermath were controversial. A faction called the Continental Democrats had advocated annexing all of Mexico, some arguing that Mexico should be punished for its behavior. Others, largely in the North, denounced the war variously as imperialism and as a pro-slavery stratagem to add more slave territory to the United States.

Alaska

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In 1867, President Andrew Johnson purchased the territory of Alaska from the Russian Empire for seven million dollars—approximately two cents per acre ($500/km²). It was the first-acquired piece of American territory not contiguous to the pre-existing territory of the United States. At the time, the purchase of Alaska was almost universally criticized, with such pejoratives as "Johnson's Polar Bear garden," "Seward's Icebox," or "Seward's Folly," for Secretary of State William H. Seward, who negotiated the deal.

See also

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• United States territorial acquisitions
• Indian Wars

References

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• Perkins, Bradford. The Cambridge History of American Foreign Relations, Vol. I, The Creation of a Republican Empire, 1776-1865. Cambridge, Eng., 1993.
• Weeks, William Earl. Building the Continental Empire: American Expansion from the Revolution to the Civil War. Chicago: Ivan R. Dee, 1996. ISBN 1566631351.
• Weinberg, Albert K. Manifest Destiny: A Study of Nationalist Expansionism in American History. Baltimore: Johns Hopkins, 1935.

External links

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• "Expansion, Continental and Overseas", article by William Appleman Williams

History of United States expansionism