What was the name of the other group of moundbuilders who lived in between the years 800 and 1500?

The other group of mound builders who lived between 800 and 1500 were primarily the Mississippian culture. They are known for constructing large, complex earthen mounds for ceremonial, religious, and political purposes, with notable sites like Cahokia in present-day Illinois. The Mississippian culture thrived in the southeastern United States, engaging in agriculture and trade, and had a significant influence on the region's social and political structures.