The Coosa chiefdom was centered along the Coosawattee River in present-day Gordon and Murray counties in northwestern Georgia. The capital of Coosa, as a modern archaeological site it is known as "Little Egypt", had a large plaza and three platform mounds, as well as residential dwellings. Researchers have found various Mississippian culture pottery types, the most substantial of which reflect the site's Middle and Late South Appalachian Mississippian culture (a regional variation of the Mississippian culture) habitation from 1300 to 1600. Archeologists have defined these as the Dallas,
Mouse Creek phases of pottery. These type variations could indicate that the chiefdom underwent three archaeological phases and changes in culture, each with distinct pottery and artifact styles. Only one other village had a mound; the others associated with the chiefdom had only residential dwellings.
Hernando de Soto and his expedition entered the Coosa chiefdom in 1540. Chroniclers recorded that the chiefdom then consisted of eight villages. Archaeologists have identified the remains of seven of these, including the capital. The population of the Coosa is thought to have been between about 2,500 to 4,650 people. The chief of Coosa ruled over a significantly wider confederation of other chiefdoms, whose territory spread 400 miles along the Appalachian Mountains across northern Georgia into eastern Tennessee and central Alabama, and whose populations totaled in the tens of thousands. This "paramount chiefdom consisted of seven or more smaller chiefdoms, representing about 50,000 people."
Coosa Historical Marker along Coosa River, outside Childersburg
Following contact with Europeans and the associated introduction of Old World diseases, the populations of the Coosa and other local chiefdoms suffered extensive fatalities; the societies went into precipitous decline. By the close of the 16th century, most of the core area of the Coosa was abandoned. The surviving population withdrew to a few villages along the Coosa River in Alabama.
Northern Georgia was occupied by the Cherokee in the early 18th century, but later abandoned. During the French and Indian War (also known as the Seven Years' War), a contingent of Muskogee under a chief named The Mortar reoccupied the site in 1759 in support of Ostenaco and the other pro-French Cherokee. By the mid-1780s, the site was occupied by Cherokee.