Pachacuti builds Terrace Farms and Qhapaq Ñan to grow sprawling mountain cities.

The Inca’s civilization home is mountain terrain. Their citizens can work these tiles and gain additional yields for doing so. Terrace Farms help make their mountain cities grow even larger. Pachacuti as a leader of Inca allows them to construct Qhapaq Ñan. This improvement allows the Inca to traverse the mountains much sooner than other civilizations. Pachacuti also gives their mountain cities greater trade income.

Pachacuti brought the Inca from relative obscurity in their city-state of Cusco to become one of the most organized, powerful, and industrious civilizations of the Americas. Under his reign, the Inca began the process of conquest and diplomatic consolidation that would serve to bring their empire to its height. Most Inca records were oral, and there was a significant loss of cultural history with the disintegration and collapse of the Inca Empire in the 16th Century. Consequently, we have relatively few details on the remarkable life of Pachacuti.

By tradition, he is numbered the ninth ruler of Cusco. Born Cusi Yupanqi, a younger son of Inca Viracocha, he was not in line to inherit the throne. At one point, the neighboring Chanka tribe invaded Cusco, and Viracocha and his chosen heir fled, while Cusi Yupanqi remained behind to organize the successful defense of Cusco. The legend is that “the very stones rose up to defend Cusco,” leading to Pachacuti's new name, which means “earth-shaker” in Quechua.

This victory had the salutary effect of raising his esteem in the eyes of the population and securing himself the chieftaincy upon Viracocha's death. Pachacuti immediately embarked on a campaign of expansion and conquest. Potential subjects were offered an opportunity to incorporate peacefully into the empire, and enjoy the benefits of social organization and material riches. If they accepted, their rulers were brought to Cusco and instructed in Inca governance, or married into Pachacuti's family. If they rejected the overtures, they were subdued militarily.

During Pachacuti's reign, Cusco was expanded as a royal capital befitting an emperor. The Incan religion, centered on the sun god, Inti, was expanded, and the role of the priesthood was further codified within the Empire. Pachacuti himself is credited with composing a number of hymns to the Inca pantheon, which were later recorded by Spanish writers during the colonial period. He may also have established the Inti Raymi holiday, celebrating the start of the new year in the Andes. Pachacuti was a prolific builder. He directed the construction of the massive royal estate at Machu Picchu, as well as irrigation projects, terrace farms, and systems of roads and travelers' hostels.

When Pachacuti died in 1471, power transferred peacefully to his son, Tupac Inca Yupanqi, who had served as either co-regent or battlefield commander during his father's reign. Future Sapa Inca were unable to leave uncontested successions, further burnishing Pachacuti's reputation.

During his lifetime, Pachacuti established the basic pattern of Inca rule: Strong but competent central authority, a highly organized population, and use of the mit'a system of labor in support of public works. But he was also willing to displace large numbers of lower-class people in order to serve his wishes for the empire, and the Inca were willing to engage in war to expand their holdings. Still, he began a remarkable life with no expectation that he would rule, and when he died, the Inca were on the march to become one of the largest civilizations of the New World.