A
mericans were on the move in the mid-nineteenth
century, in every sense of the word. Beginning in the
1830s, westering migrants began to claim land in
Texas, Oregon, and Utah, well before those regions
were part of the United States. A few years later, prospectors
from around the world descended upon the gold fields of
California, just months after that territory was acquired
from Mexico. The growing demand for labor in the emerging
industrial centers of the north drew thousands of Americans
off the farm, while millions of Europeans joined them in search
of greater opportunity.
While migration is often narrated in terms of liberation,
for many it signaled a profound loss of freedom. President
Andrew Jackson made room for land-hungry settlers and
prospectors in Georgia by dispossessing Native Americans
and sending them west. Planters establishing new cotton
and sugar plantations in Mississippi, Louisiana, and Texas
forced the sale and migration of hundreds of thousands of
slaves from the upper to the lower South. Nearly 300,000
prospectors, farmers, and Mormons heading to the Far
West dramatically disrupted Native American lands on the
Great Plains.
Several of the maps in this chapter explore the relationship
between nineteenth-century migration and national
expansion. Much of this expansion was driven by technological
innovation and the rise of a market economy. As shown on
page 120, the Erie Canal enabled farmers to produce not
just for their own subsistence and barter but also for distant
markets. Similarly, Eli Whitney’s cotton gin significantly
expanded the amount of land cultivated in the South, so that
by 1860 one-third of the nation’s cotton crop was grown west
of the Mississippi River. This increase in cultivation stimulated
Northern textile manufacturing, which in turn made cotton
the nation’s largest export. In 1858 James Henry Hammond
declared that “Cotton is king,” meaning that not even the
English monarchy could challenge the economic might of the
American South. By then the US was producing 75 percent of
the world’s cotton supply.
Westward expansion was often led by migrants who
crossed national borders to settle new land. In the 1820s
Moses Austin led a group of Southerners to Tejas (the
territory of today’s Texas) at the invitation of Mexico, which
hoped to stabilize and develop its northern frontier. In 1836
those migrants joined with Mexican-born settlers to declare
themselves independent. Many in this new Republic of
Texas sought annexation by the United States, but American
presidents were understandably reluctant to provoke war with
Mexico or antagonize Northerners who keenly opposed the
entry of a new slave state into the Union.
Just north of Texas, Congress organized a territory
dedicated to the “civilized” tribes displaced by the Indian
Removal Act of 1830. The map on page 130 shows the
geopolitics—not to mention the injustice—involved in
President Jackson’s policy of removal. The War Department
was responsible for protecting these emigrant tribes, while
also separating them from white settlers to the immediate east
in Arkansas and Missouri. The result was a complex hierarchy
of internal and external boundaries that continued to shift as
the nation expanded westward in the 1840s.
The annexation of Texas in 1845 prompted a controversial
war with Mexico, and commercial firms quickly issued maps to
meet public demand (page 134). At the same time, the federal
government issued detailed maps to encourage overland
migration to Oregon and ultimately American control of that
territory (page 132). The subsequent victory over Mexico
in 1848 gave the United States control over California, the
Intermountain West, and an enlarged Texas. The timing was
remarkable: no sooner had the US acquired California than
gold was discovered at the foothills of the Sierra Nevada
Mountains. Within weeks the US military had sponsored
the most detailed map yet of those mining districts
(page 136). Each of these three maps was designed to
advance the nation’s control over the Far West.
Some Americans celebrated this dramatic territorial
growth as a sign of Providence, while others worried that
it only extended the life of slavery. As slavery grew, so too
did Southern regional distinctiveness. In response, many
Northerners began to assert a contrary identity, one grounded
in the principle of “free labor.” To be sure, the concept of
“free labor” was more than a little ironic given that low-wage
jobs proliferating in the North gave workers little mobility.
However, by 1850, sectional differences were undeniable.
As the map on page 138 shows, waves of German and
Irish immigrants sought the harbors of Boston, New York,
Expansion, Fragmentation, and Reunification