Many pre-Columbian civilizations established permanent or urban settlements, agriculture, and complex societal hierarchies. In North America, indigenous cultures in the Lower Mississippi Valley during the Middle Archaic period built complexes of multiple mounds, with several in Louisiana dated to 5600–5000 BP. Watson Brake is considered the oldest, multiple mound complex in the Americas, as it has been dated to 3500 BC. It and other Middle Archaic sites were built by pre-ceramic, hunter-gatherer societies. They preceded the better known Poverty Point culture and its elaborate complex by nearly 2,000 years. The Mississippi Valley mound-building tradition extended into the Late Archaic period, longer than what later southeastern mound building dependent on sedentary, agricultural societies. Some of these civilizations had long ceased to function by the time of the first permanent European arrivals, and are known only through archaeological investigations or oral history from nations today. Others were contemporary with this period, and are also known from historical accounts of the time. A few, such as the Olmec, Maya, Mixtec, and Nahua had their own written records. However, most Europeans of the time viewed such texts as heretical and burned most of them. Only a few documents were hidden and thus remain today, leaving modern historians with glimpses of ancient culture and knowledge. From both indigenous American and European accounts and documents, American civilizations at the time of European encounter possessed many impressive attributes, having populous cities, and having developed theories of astronomy and mathematics. Where they persist, the societies and cultures which gave rise to these civilizations continue to adapt and evolve; they also uphold various traditions and practices which relate back to these earlier times, even if combined with those more recently adopted. Human sacrifice was a religious practice principally characteristic of pre-Columbian Azteccivilization, although other Mesoamerican civilizations like the Maya and the Zapotec practiced it as well. The extent of the practice is debated by modern scholars.
Northern America
Paleo-Indians, c. 18,000–8000 BC
*Clovis
*Folsom tradition
*Plano cultures
*Cody complex
Archaic Period, 8000–1000 BC
*Paleo-Arctic Tradition, 8000–5000 BC, Alaska and Yukon
*Watson Brake and Lower Mississippi Valley mounds sites, 3500 BC–2800 BC, Louisiana, Mississippi and Florida
*Poverty Point culture, 2200 BC–700 BC, Lower Mississippi Valley and surrounding Gulf coast
Post-archaic period, 1000 BC–onward
*Southwest:
**Ancestral Pueblo culture, 1200 BC–1300 AD, Utah, Arizona, Colorado, New Mexico—one of these cultural groups referred to as Anasazi
**Fremont culture, 1 AD–1300 AD, Utah and parts of Nevada, Idaho and Colorado
**Hohokam, 1 AD–1450 AD, Arizona
*Eastern Woodlands
**Woodland period, 1000 BC–1000 AD
***Adena, 1000–200 BC, Ohio, Indiana, West Virginia, Kentucky, and parts of Pennsylvania and New York.
***Hopewell culture, 200 BC–500 AD, Southeastern Canada and eastern United States
***Troyville culture, 400–700 AD, Louisiana and Mississippi
***Coles Creek culture, 700–1200 AD, Arkansas, Louisiana and Mississippi
