Today it is taken for granted that the United States spans from the
Atlantic Ocean to the Pacific Coast and has defined borders with Mexico
and Canada. When the country was founded in the late eighteenth century, however, the future size of the nation was by no means apparent. In
1790, 95 percent of Americans lived east of the Appalachian Mountains,
which served as the western border of the original thirteen colonies. The
United States held less than 900,000 square miles of territory on the
eastern seaboard—far less than the 3.5 million square miles the country
occupies today. Lands west of the Appalachians were claimed by native
peoples and various European nations.
As soon as the nation won its independence, the American people
began looking for new places to settle. Eager to spread “American ideals,”
expansionists, people who wanted to see the nation expand its borders,
looked to the vast regions west and south of the original thirteen states.
Two vast regions had been added to the United States by the early nineteenth century: the Northwest Territory (present-day Illinois, Indiana,
Michigan, Ohio, Wisconsin, and part of Minnesota) and the Louisiana
Territory (present-day Arkansas, Iowa, Louisiana, Missouri, Nebraska,
North Dakota, Oklahoma, South Dakota, and parts of Colorado,
Kansas, Minnesota, Montana, and Wyoming).
American expansionism was fueled by the young nation’s population
growth. Pioneer settlement in the Northwest Territory resulted in an
increase in farmland and overall crop production. A continuous influx of
immigrants from Europe supplied more farmers and farm workers, as
well as laborers for the factories that had opened across New England
and the Mid-Atlantic. The population grew rapidly. In the two decades
between 1840 and 1860 alone, the U.S. population more than doubled,
increasing from about 17 million to more than 38 million. As the eastern seaboard cities grew, a system of new canals, steamboats, roads, and
railroads also opened up the interior to increased settlement. By 1850,
almost half the population lived outside the original thirteen states.
An American destiny
The idea of Manifest Destiny had emerged around the 1820s. Speaking
for millions of Americans, President John Quincy Adams (1767–1848;
served 1825–29) maintained that it was God’s will that a large and powerful United States would encompass the entire North American continent. This emerging concept included a sense of moral virtue—that
Americans had the God-given mission to expand and develop the continent. He also expressed that it was a natural right to grow and to prosper while doing so—that this was nothing short of the “pursuit of
happiness” promised in the Declaration of Independence.
Journalist John L. O’Sullivan (1813–1895) first coined the term
“Manifest Destiny” in 1845 in an article he wrote for the United States
Magazine and Democratic Review. He described Manifest Destiny as the
nation’s divine and historical destiny “to overspread the continent allotted by Providence [God’s design] for the free development of our yearly
multiplying millions” (as quoted in Reginald C. Stuart’s book United States Expansionism and British North America, 1775–1871). Behind
O’Sullivan’s noble description of Manifest Destiny lay more basic human
motivations: the hungering for riches, the longing to possess land, and
the search for a good life—the dream of the West’s common man.
Expansionists argued that American democracy itself depended on widespread landownership.
Whose natural rights?
The expansion advocated by the doctrine of Manifest Destiny came at
the expense of other people, especially Native Americans and Mexicans
in the Southwest, whose destinies and natural rights were often overlooked by the American public. Manifest Destiny was often used as a
rationalization, or excuse, for trampling upon the rights—as well as the
lands and resources—of others. One pro-expansion faction, led by U.S.
senator Thomas Hart Benton (1782–1858) of Missouri, voiced a decidedly racist justification for taking the land. “It would seem that the
White race alone received the divine command to subdue and replenish
the earth,” Benton wrote in 1846, as quoted by Page Stegner in Winning
the Wild West: The Epic Saga of the American Frontier, 1800–1899. He
said that unless Native Americans could adapt to the civilization brought
by U.S. settlers, they faced certain destruction.
The concept of expanding the country’s borders to include such a
large amount of territory was by no means shared by all. The Whig
Party believed that trying to govern too much territory might, in the
long run, destroy the new government. Many believed that trying to
reach the western shores of the continent by land was hopelessly dangerous. To settle those uncivilized lands by bringing women and children to
them was considered savage.
Realizing the ideal
The fervor of Manifest Destiny was perhaps best illustrated by the U.S.
expansion into Oregon and California. In the 1830s, other nations
ruled the two sparsely populated areas: Oregon by England and
California by Mexico. Expansionists advertised the areas as heavenly,
ideal places, spawning in many people an urgent desire, or “fever,” to
migrate, despite the many hardships of traveling through the wilderness
and settling beyond the reaches of American civilization. During the
1840s, the United States gained control of both regions.
Between 1845 and 1848, with the annexation (addition) of the
independent Republic of Texas and the acquisition of the vast Southwest
Territory after the Mexican-American War (1846–48), the United
States acquired more than one million square miles of land. In 1853,
southern Arizona was acquired from Mexico, completing the acquisition
of the territory that would eventually become the contiguous United
States (all but Alaska and Hawaii).