Powerful Muskogean-speaking Mississippian paramount chiefdom centered on the Coosawattee River in northwestern Georgia, dominating a network of subordinate chiefdoms across present-day Georgia, Tennessee and Alabama.
Visited and described by three Spanish expeditions (de Soto 1540, Luna 1560, Pardo 1567) before disease and disruption fragmented it by 1600; the Coosa name survived as one of the four Muscogee Creek 'mother towns.'
Dedicated archaeological/historical monograph on exactly this chiefdom's rise, contact-era encounters, and collapse.