The history of Wisconsin includes stories of people who have lived in Wisconsin since it became a state of the U.S. in 1848, the Native American tribes who made their homeland in Wisconsin, the French and British colonists who were the first Europeans to live there, and the American settlers who lived in Wisconsin when it was a territory.

Since its admission to the Union on May 29, 1848, as the 30th state, Wisconsin has been ethnically heterogeneous, with Yankees being among the first to arrive from New York and New England. They dominated the state's heavy industry, finance, politics and education. Large numbers of European immigrants followed them, including German Americans, mostly between 1850 and 1900, Scandinavians (the largest group being Norwegian Americans) and smaller groups of Belgian Americans, Dutch Americans, Swiss Americans, Finnish Americans, Irish Americans and others; in the 20th century, large numbers of Polish Americans and African Americans came, settling mainly in Milwaukee, as well as Hmong Americans in Eau Claire and Appleton.

The first known inhabitants of what is now Wisconsin were Paleo-Indians, who first arrived in the region in about 10,000 BC at the end of the Ice Age. The retreating glaciers left behind a tundra in Wisconsin inhabited by large animals, such as mammoths, mastodons, bison, giant beaver, and muskox. The Boaz mastodon and the Clovis artifacts discovered in Boaz, Wisconsin show that the Paleo-Indians hunted these large animals. They also gathered plants as conifer forests grew in the glaciers' wake. With the decline and extinction of many large mammals in the Americas, the Paleo-Indian diet shifted toward smaller mammals like deer and bison.

During the Archaic Period, from 6000 to 1000 BC, mixed conifer-hardwood forests as well as mixed prairie-forests replaced Wisconsin's conifer forests. People continued to depend on hunting and gathering. Around 4000 BC they developed spear-throwers and copper tools such as axes, adzes, projectile points, knives, perforators, fishhooks and harpoons. Copper ornaments like beaded necklaces also appeared around 1500 BC. These people gathered copper ore at quarries on the Keweenaw Peninsula in Michigan and on Isle Royale in Lake Superior. They may have crafted copper artifacts by hammering and folding the metal and also by heating it to increase its malleability. However it is not certain if these people reached the level of copper smelting. Regardless, the Copper Culture of the Great Lakes region reached a level of sophistication unprecedented in North America. The Late Archaic Period also saw the emergence of cemeteries and ritual burials, such as the one in Oconto.

The Early Woodland Period began in 1000 BC as plants became an increasingly important part of the people's diet. Small scale agriculture and pottery arrived in southern Wisconsin at this time. The primary crops were maize, beans and squash. Agriculture, however, could not sufficiently support these people, who also had to hunt and gather. Agriculture at this time was more akin to gardening than to farming. Villages emerged along rivers, streams and lakes, and the earliest earthen burial mounds were constructed. The Havana Hopewell culture arrived in Wisconsin in the Middle Woodland Period, settling along the Mississippi River. The Hopewell people connected Wisconsin to their trade practices, which stretched from Ohio to Yellowstone and from Wisconsin to the Gulf of Mexico. They constructed elaborate mounds, made elaborately decorated pottery and brought a wide range of traded minerals to the area. The Hopewell people may have influenced the other inhabitants of Wisconsin, rather than displacing them. The Late Woodland Period began in about 400 AD, following the disappearance of the Hopewell culture from the area. The people of Wisconsin first used the bow and arrow in the final centuries of the Woodland Period, and agriculture continued to be practiced in the southern part of the state. The effigy mound culture dominated Southern Wisconsin during this time, building earthen burial mounds in the shapes of animals. Examples of effigy mounds still exist at High Cliff State Park and at Lizard Mound County Park. In northern Wisconsin people continued to survive on hunting and gathering, and constructed conical mounds.

People of the Mississippian culture expanded into Wisconsin around 1050 AD and established a settlement at Aztalan along the Crawfish River. While begun by the Caddoan people, other cultures began to borrow & adapt the Mississippian cultural structure. This elaborately planned site may have been the northernmost outpost of Cahokia, although it is also now known that some Siouan peoples along the Mississippi River may have taken part in the culture as well.

Both Woodland and Mississippian peoples inhabited Aztalan, which was connected to the extensive Mississippian trade network. Shells from the Gulf of Mexico, copper from Lake Superior and Mill Creek chert have been found at the site. Aztalan was abandoned around 1200 AD. The Oneota people later built agriculturally based villages, similar to those of the Mississippians but without the extensive trade networks, in the state.

By the time the first Europeans arrived in Wisconsin, the Oneota had disappeared. The historically documented inhabitants, as of the first European incursions, were the Siouan speaking Dakota Oyate to the northwest, the Chiwere speaking Ho-Chunk (Winnebago) and the Algonquian Menominee to the northeast, with their lands beginning approximately north of Green Bay. The Chiwere lands were south of Green Bay and followed rivers to the southwest. Over time, other tribes moved to Wisconsin, including the Ojibwe, the Illinois, the Fauk, the Sauk and the Mahican., with the Mahican being one of the last groups to arrive.