Manifest Destiny Key Facts

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Manifest Destiny, in U.S. history, was the belief in the supposed inevitability of the United States expanding its borders westward across the North American continent to the Pacific Ocean and beyond. In the 19th century the idea of Manifest Destiny resulted in extensive territorial expansion.

The term manifest destiny was first used in 1845 by editor John L. O’Sullivan. He did not think it an especially profound phrase. Rather, it was buried in a long essay of his that appeared in the July–August issue of The United States Magazine, and Democratic Review. In that essay he spoke of America’s “manifest destiny to overspread the continent allotted by Providence for the free development of our yearly multiplying millions.” O’Sullivan was arguing for the annexation of Texas and criticizing what he saw as European interference in American expansion. O’Sullivan used the term again in a column for the New York Morning News that was published on December 27. This time his reference to divine superintendence garnered wider notice and began to generate debate.

Manifest means “clear or obvious,” and destiny refers to events that will certainly happen in the future.

Louisiana PurchaseThe land that the United States purchased from France in 1803 included all or part of 15 present-day states. After negotiations between the United States and Spain, the southwestern boundary of the territory was changed in 1819. With its final boundaries, the Louisiana Purchase included all or part of 13 modern states.
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Westward movement had been part of American history since the time of English colonization. U.S. President Thomas Jefferson’s deal with the French in 1803, the Louisiana Purchase, doubled the size of the country.

In the mid-1800s Manifest Destiny became a rallying cry as well as a rationale for U.S. foreign policy. Democrats took up Manifest Destiny as a slogan. The term had religious meaning for many, as they felt it was God’s will for the United States to take over the lands to the west.

Many Americans, including many in the Whig Party, were initially against Manifest Destiny. Some had humanitarian concerns about relocating already settled Indian nations. Others doubted the country’s ability to rule such an extensive empire.

American frontierAn 1846 map of the western United States.
Library of Congress, Geography and Map Division, Washington, D.C. (g4050 ct000603)

In the 1840s the United States and Britain settled a land dispute in western North America. Through diplomacy the two countries accepted the 49th parallel as the boundary between the United States and Canada. That made the Oregon Country a U.S. territory.

Examine how U.S. westward movement and the annexation of Texas sparked the Mexican-American WarBegun when the United States annexed Texas, the Mexican-American War ended with the United States acquiring much of what is now the American Southwest.
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The U.S. victory in the Mexican-American War (1846–48) resulted in the Treaty of Guadalupe Hidalgo. The treaty gave the United States more than 525,000 square miles (1,360,000 square kilometers) of Mexican territory. This land included most of what are now Arizona, California, Nevada, New Mexico, Texas, Utah, and western Colorado.

Oregon Trail: mapThe Oregon Trail stretched for some 2,000 miles from what is now Missouri westward to what is now northern Oregon.
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Hundreds of thousands of people traveled west for the chance to own land and other opportunities. Common routes such as the Oregon Trail, Santa Fe Trail, and Mormon Trail saw regular traffic of wagons carrying people and their belongings to their new lives.

The acquisition of new western territories revived arguments among the states over slavery. In fact, those disputes brought the era of Manifest Destiny to an abrupt close.

Gadsden PurchaseA U.S. postage stamp commemorates the Gadsden Purchase. It was issued in 1953, a hundred years after the purchase was made.
© spatuletail/Shutterstock.com

Plans were underway to tie the eastern United States to the Pacific Coast with a transcontinental railroad. This led to the country’s final land acquisition before the American Civil War (1861–65). U.S. Minister to Mexico James Gadsden purchased a parcel of land (present-day southern Arizona and southern New Mexico) in 1853 for a southern railroad route. The idea that it would travel through the slaveholding South provoked the North. Americans soon found themselves involved in additional arguments that postponed further expansion.

Spanish-American WarU.S. soldiers occupy a position near Manila, in the Philippines, during the Spanish-American War (1898).
© Hulton Archive/Getty Images

After the Civil War the concept of Manifest Destiny was briefly revived on a few occasions. For example, in 1867 the United States purchased Alaska from Russia. In what was called the “New Manifest Destiny,” the United States acquired territory outside of North America. In 1898 Spain and the United States signed the Treaty of Paris, ending the Spanish-American War. As a result the United States acquired Spanish territories in the western Pacific and Latin America. That same year the United States annexed Hawaii.

Manifest Destiny Timeline

Manifest Destiny | Timeline

Causes and Effects of Manifest Destiny

Manifest Destiny | Causes & Effects