The Alibamu and the Coushatta, who lived on the opposite side the river, were descended from the Mississippian culture, which had built massive earthwork mounds as part of their society about 950--1250 AD.
The Alibamu were descended from the Mississippian culture. The Coushatta were descended from the Mississippian culture. The Mississippian culture had built massive earthwork mounds as part of their society about 950--1250 AD. The Alibamu lived on the opposite side the river. The Coushatta lived on the opposite side the river.