The Mississippian culture is a mound-building Native American culture that flourishes in what is now the Midwestern, Eastern, and Southeastern United States from approximately 800 to 1500 CE, varying regionally.

The Mississippian way of life began to develop in the Mississippi River Valley (for which it is named).

Cultures in the tributary Tennessee River Valley may have also begun to develop Mississippian characteristics at this point.

Almost all dated Mississippian sites predate the de Soto expedition of 1539-40, with notable exceptions being Natchez communities that maintain Mississippian cultural practices into the 18th century.