The Sapa Inca, a Quechua title meaning the only Inca or unique Inca, ruled the Inca state as its supreme political and religious authority, understood within Inca religion as a direct descendant of Inti, the sun god, and therefore as sacred in his own person. This claimed descent legitimated Inca rule over the many distinct peoples the empire, called Tawantinsuyu, the Four Regions, came to incorporate through conquest and alliance across the Andes, and the Sapa Inca's mummified predecessors were preserved and ceremonially attended after death, continuing to hold land and participate symbolically in state affairs, a distinctive Andean practice with few direct parallels among the other monarchies in this record.
Inca tradition traced the dynasty's founding to Manco Capac, a legendary first Sapa Inca said to have emerged, in differing versions of the myth, from either Lake Titicaca or a cave at Pacaritambo, sent by Inti to found a civilized society. Historians place the actual emergence of an Inca state in the Cuzco valley around the thirteenth century CE, with rapid imperial expansion beginning under Pachacuti in the mid fifteenth century, transforming a regional polity into the largest empire pre-Columbian South America produced.