Santee is the newest confederate state of the Mississippian Confederation, admitted under the reign of Christophe the Christian in 1568, ten years after the Confederation was established.
The Santee are both part of the Mississippian Confederation and the Seven Fires Council of Sioux people. As such, the Great Chief of Mississippia gets a seat at the Seven Fires Council. The Santee are Sioux, an evolved form of Mississippian culture.