The geographical and economic expansion that marked the period from 1790 to 1820 inspired scientific and technological advances as well as literary and artistic tributes to a distinctly American identity. For young ambitious men like Parker Cleaveland, Eli Whitney, Washington Irving, and Meriwether Lewis, the opportunities that opened in education, science, literature, and exploration offered possibilities for fame and financial success. While Whitney, Irving, and Lewis traveled widely, Cleaveland remained a professor of mathematics, mineralogy, and chemistry at Bowdoin, dying in Brunswick, Maine, in 1858.

Lewis’s efforts to open up the Louisiana Territory transformed the lives of many Americans. Along with the construction of roads, the invention of steamboats, and the introduction of iron plows, his Corps of Discovery opened up new lands for farming and also fueled the rise of western cities. Many white families sought fertile land, abundant wildlife, or opportunities for trade on the frontier. Yet these families often had to purchase land from speculators or compete with wealthy planters. And those who carved out farms might face Indians angered by the constant encroachment of white Americans on their lands.

New opportunities also appeared in eastern towns and cities as investors, inventors, and skilled artisans established factories and improved transportation. White women of middling or elite status could attend female academies, enter marriages based on ideals of companionship and mutual responsibilities, purchase rather than make cotton thread and cloth, and retain servants to perform the heaviest work. Yet these changes occurred gradually and unevenly. And while poorer white women might more easily find jobs in cotton mills or as servants, the pay was low and the hours long.

Transformations in white society introduced even more difficult challenges for African Americans. Despite the introduction of gradual emancipation in the North and the end of the international slave trade, slavery continued to grow. The invention of the cotton gin ensured the expansion of cotton cultivation into new areas, and many slaves were forced to move west and leave family and friends behind. Enslaved women and men honed means of survival and resistance, but few could imagine a revolution like the one that took place in Haiti.

At the same time, all along the expanding U.S. frontier, American Indians faced continued pressure to leave their lands, embrace white culture, or both. In 1810 Sacagawea, Charbonneau, and their son Baptiste apparently traveled to St. Louis at the invitation of William Clark, who offered to pay for Baptiste’s schooling. Sacagawea left Baptiste in Clark’s care, and it is not clear whether she ever saw her son again. William Clark wrote “Se car ja we au Dead” on the cover of his cash book for 1825–1828, suggesting that she died during those years. By then, the Shoshone and Hidatsa were facing the onslaught of white settlement. They, along with Indians living in areas like Georgia, the Carolinas, and Tennessee, continued to resist U.S. expansion and struggled to control the embattled frontier.

Indeed, the United States remained embattled throughout the early years of the republic. From 1790 to 1820, Great Britain, France, and the Barbary States of North Africa constantly challenged U.S. sovereignty from abroad while debates over slavery and conflicts over Indian lands multiplied at home. Moreover, as federal power expanded under Democratic-Republic rule, some Americans continued to worry about protecting the rights of states and of individuals. The American identities forged in the early republic would be continually tested as new challenges emerged and older conflicts intensified in the following decades.