The history of the United States begins long before European settlement, with Paleo-Indians spreading across North America and developing farming, permanent villages, trade networks, pueblos, and powerful confederacies such as the Iroquois. Indigenous societies also flourished in Hawaii and Puerto Rico. European contact brought an exchange of plants and animals, but Eurasian diseases devastated Native populations, while colonization produced warfare, dispossession, and forced migration.
Spanish, Dutch, Swedish, French, and English settlements emerged. Jamestown survived through tobacco, Plymouth and Massachusetts grew from religious migration, and the Southern Colonies developed plantation economies dependent on African slavery. British taxation after the French and Indian War provoked resistance, leading to the Revolutionary War, independence, the Constitution, and a stronger federal government.
The young republic expanded through the Louisiana Purchase, annexation, war with Mexico, and the ideology of manifest destiny. This growth intensified the struggle over slavery. Southern secession produced the Civil War, whose Union victory preserved the nation and abolished slavery. Reconstruction briefly expanded Black citizenship and voting rights, but its end enabled Jim Crow segregation and white-supremacist violence.
Railroads, immigration, industrialization, labor conflict, and Progressive reforms transformed the country. The United States joined World War I, endured the Great Depression, and used the New Deal to create lasting social programs. Pearl Harbor brought entry into World War II, after which the nation emerged as a superpower. The Cold War brought alliances, proxy wars, civil rights victories, social movements, and the Space Race. Since 1991, the country has faced terrorism, recession, pandemics, polarization, democratic strain, overseas conflicts, and renewed efforts to return humans to the Moon.