Sacagawea must have realized that the expedition she accompanied was a harbinger of white expansion, but many Indians only gradually came to realize that the few dozen men who joined Lewis and Clark heralded the arrival of hundreds and then thousands of migrants from the East. As white Americans encroached farther and farther on lands long settled by native peoples, Indian tribes in the eastern United States and the midsection of the nation were forced westward. As early as 1800, groups like the Shoshones, who originally inhabited the Great Plains, had been forced into the Rocky Mountains by Indians moving into the plains from the Mississippi and Ohio valleys (Map 8.2).

At the same time, although the vast majority of Americans continued to live in rural areas, a growing number moved to cities (defined as places with 8,000 or more inhabitants). New York City and Philadelphia both counted more than 100,000 residents by 1810. In New York, immigrants, most of them Irish, made up about 10 percent of the population in 1820 and twice that percentage five years later. During this time, the number of African Americans in New York City increased to more than 10,000. New cities began to emerge along the nation’s frontier as well. After the United States acquired the Louisiana Territory, New Orleans grew rapidly, and western migration fueled the development of Cincinnati. Even smaller frontier towns served important functions for migrants traveling west. Trading posts appeared across the Mississippi valley, which eased the migration of thousands headed farther west. They served as sites of exchange between Indians and white Americans and created the foundations for later cities (Table 8.1).

Source: Will Leinicke, Marion Lardner, and Ferrel Anderson, Two Nations, One Land (Rock Island, IL: Citizens to Preserve Black Hawk Park, 1981).

Most Americans who headed west hoped to benefit from the increasingly liberal terms offered by the federal government for purchasing land. Yeomen farmers sought sufficient acreage to support their families and grow some additional crops for sale. They were eager to settle in western sections of the original thirteen states, in the Ohio River valley, or in newly opened territories along the Missouri and Kansas Rivers. In the South, small farmers had to compete with slave-owning planters who headed west in the early nineteenth century. Migrants to the Mississippi valley also had to contend with a sizable population of long-settled Spanish residents and French planters who had taken refuge from Saint Domingue with their slaves, as well as Chickasaw and Creek Indians in the South and Shawnee, Chippewa, Sauk, and Fox Indians farther north.

The development of roads and turnpikes hastened the movement of people and the transportation of goods. Frontier farmers required methods to get their produce to eastern markets quickly and cheaply. Before completion of the Lancaster Turnpike in Pennsylvania, it cost as much to carry wheat and other items overland the sixty-two miles to Philadelphia as it did to ship them by sea from Philadelphia to London. Those who lived farther west faced even greater challenges. With the admission of Kentucky (1792), Tennessee (1796), and Ohio (1803) to the Union, demands for congressional assistance in building transportation routes grew louder. By 1819 five more states were admitted along the Mississippi River, from Louisiana to Illinois.

During Jefferson’s administration, Albert Gallatin urged Congress to fund internal improvements—that is, roads and canals—to enhance the economic development of the nation. Legislatures chartered and sometimes helped fund improved transportation in their own states, but Gallatin focused on transportation across regions. He advocated a “great turnpike road” along the Atlantic seaboard from Maine to Georgia as well as roads to connect the four main rivers that flowed from the Appalachians to the Atlantic Ocean. In 1815 Congress approved funds for one such project, the National Road from western Maryland through southwestern Pennsylvania to Wheeling, West Virginia. This so-called Cumberland Road was completed in 1818, and in the following decades it was extended into Ohio and Illinois.

Carrying people and goods by water was even faster and cheaper than transporting them over land, but rivers ran mainly north and south. In addition, although loads could be delivered quickly downstream, the return voyage was long and slow. While politicians advocated the construction of canals along east-west routes to link river systems, inventors and mechanics focused on building boats powered by steam to overcome the problems of sending goods upriver.

Oliver Evans, a machinist in Philadelphia, developed a steam-powered gristmill—to produce flour from grain—in 1788. Then in 1804 he invented a high-pressure steam engine attached to a dredge that cleaned the silt around the docks in Philadelphia harbor. He had insufficient funds, however, to pursue work on a steam-powered boat.

In New York State, Robert Fulton sought to improve on Evans’s efforts, using the low-pressure steam engine developed in England. Fulton had moved to Paris in the early nineteenth century to train as a painter. While there, he met the wealthy ambassador Robert Livingston, who helped negotiate the Louisiana Purchase. Livingston convinced Fulton to focus on engineering and provided funds for him to do so. In 1807 Fulton launched the first successful steamboat, the Clermont, which traveled up the Hudson River from New York City to Albany in only thirty-two hours. The powerful Mississippi River proved a greater challenge, but by combining Evans’s high-pressure steam engine with a flat-bottom hull that avoided the river’s sandbars, mechanics who worked along the frontier improved Fulton’s original design and launched the steamboat era in the West.