Pachacuti was the last Inca of the Kingdom of Cuzco and the first Inca of Tahuantinsuyu (Inca empire). He led the first round of conquest that led to the establishment of the Inca empire. The conquest began after a rival community attacked and was routed by his army. Pachacuti then began the era of conquest that would, within three generations, bring most of civilized South America under a single government.
In 1463 CE, he put his son Tupac Inca in charge of the Inca army , and began a political reorganization of the Kingdom of Cuzco. This resulted in the liquidation of the Kingdom of Cuzco and the establishment of Tahuantinsuyu or 'land of four corners'. Under his system, there were four apos that each controlled one of four provinces. Below these governors were t'oqrikoq, or local leaders, who ran a city, valley, or mine. By the time of the Spanish conquest of Peru, each apo had around 15 t'oqrikoq below him, but we can assume there were fewer when Pachacuti first organized this system. He also established a separate chain of command for the army and priesthood to establish a system of checks and balances on power.
While Pachacuti was reorganizing the political system, his son Tupac Inca, continued to conquer territiories to the north. By 1471 CE, when Pachacuti died, Tupac Inca had already reached what is today Equador.
Despite Pachacuti's poitical and military talents, he did not improve upon the system of choosing the next Inca. His son probably became the next Inca without any dispute, but in future generations the next Inca had to win control of the empire by winning enough support from the apos, priesthood, and military to either win a civil war or intimidate anyone else from trying to wrest control of the empire.
Conquest
In Quechua Pachacutec means earthquake, cataclysm, or he who turns the world upside down. He certainly turned his little hamlet into an empire that could compete with the Chimu, and would eventually incorporate them within the Inca empire.
