Nomadic hunters entered what is now Iowa as early as 10,000 B.C., coming on foot. Around 1000 B.C., other Indians, mound builders of the Adena culture, arrived probably by canoe or dugout. They established permanent settlements along larger streams and engaged in farming. After 1200 A.D., warlike tribes entered Iowa and displaced the mound builders of a later culture, the Mississipian. Among these later arrivals were the Iowa, Oto, and Winnebago.
| Important dates in Iowa | |
| 1673 | Louis Jolliet and Jacques Marquette of France became the first white people to see the Iowa region. |
| 1762 | France ceded part of its colony of Louisiana, including Iowa, to Spain. |
| 1788 | Julien Dubuque, Iowa's first white settler, began mining lead near present-day Dubuque. |
| 1800 | Spain ceded the Louisiana region back to France. |
| 1803 | The U.S. acquired Iowa in the Louisiana Purchase. |
| 1808 | The U.S. Army built Fort Madison. |
| 1832 | Indians led by Chief Black Hawk were defeated by the U.S. Army in the Black Hawk War. |
| 1833 | Permanent settlements began in the Iowa region. |
| 1834 | Congress attached the area to the Territory of Michigan for governmental purposes. |
| 1836 | Congress created the Territory of Wisconsin, which included Iowa, Minnesota, and most of the Dakotas. |
| 1838 | Congress created the Territory of Iowa. |
| 1846 | Iowa became the 29th state on December 28. |
| 1857 | The legislature adopted Iowa's present Constitution. |
| 1867 | The first railroad was completed across Iowa, from the Mississippi River to Council Bluffs. |
| 1873 | Grange members opposed the practices of railroads serving farmers and won control of the legislature. |
| 1913 | The Keokuk Dam was completed. |
| 1917 | Iowa began an extensive road-building program. |
| 1920's-1933 | Many Iowa farmers lost their land through failure to make mortgage payments. |
| Mid-1930's-1940's | Legislation was passed to help Iowa farmers. |
| 1962 | The Iowa court system was reorganized. |
| Mid-1970's | Manufacturing overtook agriculture as a source of income in Iowa. |
| 1985 | The state established a lottery to raise revenue. |
| 1993 | Floods caused more than $2 billion in property and crop damage in Iowa. |

