Mound builders

The varying cultures collectively called Mound Builders were inhabitants of North America who, during a 5,000-year period, constructed various styles of earthen mounds for religious and ceremonial, burial, and elite residential purposes. These included the Pre-Columbian cultures of the Archaic period; Woodland period (Adena and Hopewell cultures); and Mississippian period; dating from roughly 3500 BCE (the construction of Watson Brake) to the 16th century CE, and living in regions of the Great Lakes, the Ohio River Valley, and the Mississippi River valley and its tributary waters.

Since the 19th century, the prevailing scholarly consensus has been that the mounds were constructed by indigenous peoples of the Americas. Sixteenth-century Spanish explorers made contact with natives living in a number of later Mississippian cities, described their cultures, and left artifacts. By the time of United States westward expansion two hundred years later, Native Americans were generally not knowledgeable about the civilizations that produced the mounds. Research and study of these cultures and peoples has been based mostly on archaeology and anthropology.

At one time, the term "mound builder" was applied to the people believed to have constructed these earthworks. In the 16th through 19th centuries, Europeans and Americans generally thought that a people other than one related to the historic Native Americans had built the mounds.

The namesake cultural trait of the Mound Builders was the building of mounds and other earthworks. These burial and ceremonial structures were typically flat-topped pyramids or platform mounds, flat-topped or rounded cones, elongated ridges, and sometimes a variety of other forms. They were generally built as part of complex villages that arose from more dense populations, with a specialization of skills and knowledge. The early earthworks built in Louisiana c. 3500 BCE are the only ones known to be built by a hunter-gatherer culture.

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