The Southeastern Ceremonial Complex (formerly the Southern Cult), aka S.E.C.C., is the name given to the regional stylistic similarity of artifacts, iconography, ceremonies, and mythology of the Mississippian culture that coincided with their adoption of maize agriculture and chiefdom-level complex social organization from 1200 to 1650 CE. This development appears to have no direct links to Mesoamerica, but developed independently. This ceremonial complex represents a major component of the religion of the Mississippian peoples, and is one of the primary means by which their religion is understood.
Obsolete names for this ceremonial complex, found in some anthropological sources, include Buzzard Cult and Southern Death Cult.
Much of what is called a "complex" was more of an "exchange network." This kind of network may be illustrated by a pair of shell gorgets whose representation is so similar as to suggest that they were made by the same artist. One is found in southeast Missouri and the other in Spiro Mounds in Oklahoma. Numerous other pairs of extremely similar gorgets serve to link sites across the entire Southeast. The social organization of the Mississippian culture was based on warfare, which was represented by an array of motifs and symbols in articles made from costly raw materials, such as conches from Florida, copper from the Great Lakes area and Appalachian Mountains, lead from northern Illinois and Iowa, pottery from Tennessee, and stone tools sourced from Kansas, Texas, and southern Illinois. Such objects occur in elite burials, together with war axes, maces, and other weapons. These warrior symbols occur alongside other artifacts, which bear cosmic imagery depicting animals, humans, and mythic beasts. This symbolic imagery bound together warfare, cosmology, and nobility into a coherent whole. Some of these categories of artifacts were used as markers of chiefly office, which varied from one location to another. The term Southeast Ceremonial Complex refers to a complex, highly variable set of religious mechanisms that supported the authority of local chiefs.