In prehistoric times, the Mound Builders, a farming people, lived in the Iowa area. When Europeans first came to explore the region in the 17th cent., various Native American groups, including the Iowa, reputedly the source of the state's name, occupied the land. The Sac and Fox also ranged over the land, but it was the combative Sioux who dominated the area. In 1673 the French explorers Father Jacques Marquette and Louis Jolliet traveled down the Mississippi River and touched upon the Iowa shores, as did Robert Cavelier, sieur de La Salle, in 1681–82. The areas surrounding the Des Moines and Mississippi rivers were profitable for fur traders, and a number of Iowa towns developed from trading posts.
Late in the 18th cent. a French Canadian, Julien Dubuque, leased land from Native Americans around the Dubuque area and opened lead mines there. After his death they refused to permit others to work the mines, and U.S. troops under Lt. Jefferson Davis protected Native American rights to the land as late as 1830. However, their hold was doomed after the United States acquired Iowa as part of the Louisiana Purchase of 1803.
In 1832 the Black Hawk War broke out as the Sac and Fox, led by their chief, Black Hawk, fought to regain their former lands in Illinois along the Mississippi River. They were defeated by U.S. troops and were forced to leave the Illinois lands and cede to the United States much of their land along the river on the Iowa side. Within two decades after the Black Hawk War, all Native American lands in the region had been ceded to the United States. Meanwhile, a great rush of frontiersmen came to settle the prairies and take the mines.
Slavery was prohibited in Iowa under the Missouri Compromise of 1820, which excluded it from the lands of the Louisiana Purchase north of lat. 36°30−N. Included in the Missouri Territory prior to 1821, Iowa was subsequently part of Michigan Territory and Wisconsin Territory. By 1838, Iowa Territory was organized, with Burlington as the temporary capital. In the following year, Iowa City became the capital. The Iowans quickly built a rural civilization like that of New England, where many of them had lived. Later, immigrants from Europe, notably Germans, Czechs, Dutch, and Scandinavians, brought their agricultural skills and their own customs to enrich Iowa's rural life, and a group of German Pietists established the Amana Church Society, a successful attempt at communal social organization. A system of public schools was set up in 1839, and efforts made soon thereafter resulted in the establishment of a number of colleges and universities.
Iowa became a state in 1846, and Ansel Briggs was elected as the first governor. In 1857 the capital was moved from Iowa City to Des Moines. In that same year the state adopted its second constitution. Iowa prospered greatly with the beginning of railroad construction, and the rivalry between towns to get the lines was so fierce that the grant of big land tracts to railroad companies was curtailed by legislative act in 1857. Two years earlier the state's first railroad line was completed between Davenport and Muscatine along the eastern border. Before and during the Civil War, Iowans, generally owners of small, independent farms, were naturally sympathetic to the antislavery side, and many fought for the Union. The Underground Railroad, which helped many fugitive slaves escape to free states, was active in Iowa, and the abolitionist John Brown made his headquarters there for a time.
Iowa's farmers prospered after the Civil War, but during the hard times that afflicted the country in the 1870s they found themselves burdened with debts. Feeling oppressed by the currency system, corporations, and high railroad and grain-storage rates, many of Iowa's farmers supported, along with other farmers of the West, the Granger movement, the Greenback party, and the Populist party. The reform movements had some success in the state. Granger laws were enacted in 1874 and 1876 regulating railroad rates, but these laws were repealed in 1877 under pressure from the railroad companies. By the end of the 19th cent., times improved, and the agrarian movements declined. Farm units grew larger, and mechanization brought great increases in productivity.
Much of Iowa's society may still resemble that depicted in the paintings of Grant Wood, an Iowan, but the state's industrial economy as well as other elements of modernization have altered this image. While on a visit to the United States in 1959, Nikita S. Khrushchev, then premier of the Soviet Union, was invited to a farm in Iowa to observe part of the U.S. farm economy. The volatile nature of agricultural prices combined with a steady decline in manufacturing has made Iowa susceptible to economic recession. This was especially true in the 1980s, when Iowa was second in the United States in outmigration with a 4.7% decline in population.