Many Native American tribes migrated over the centuries in response to local conditions and intertribal warfare.
Those living in territories at the time of the European encounter were often not the descendants of peoples who had lived there centuries before and built the mounds.
Mississippian culture pottery and stone tools in the Cahokian style were found at the Silvernale site near Red Wing, Minnesota, and materials and trade goods from Pennsylvania, the Gulf Coast and Lake Superior have been excavated at Cahokia.
At the high point of its development, Cahokia was the largest urban center north of the great Mesoamerican cities in Mexico and Central America.
Today, Cahokia Mounds is considered the largest and most complex archaeological site north of the great pre-Columbian cities in Mexico.