Inca Empire

Tawantinsuyu, the Land of the Four Quarters — the largest indigenous empire ever to arise in the Americas, stretching from southern Colombia to central Chile along the spine of the Andes. From Pachacuti's reorganization of a Cuzco kingdom into an imperial system in 1438, the Inca conquered or absorbed perhaps fifteen million people in less than a century. The empire collapsed within a decade of Spanish arrival in 1532 — undermined by smallpox, civil war, and the audacity of Francisco Pizarro's seizure of the emperor at Cajamarca.