Pachacuti

According to the chronicles compiled after the Spanish conquest, Pachacuti was the ninth ruler of the Inca dynasty and the sovereign who transformed a small highland polity around Cusco into the empire the Incas called Tawantinsuyu. The Incas kept no writing, and all dates for his life and reign, including the conventional span of 1438 to 1471 and a birth around 1418, derive from colonial-era chroniclers such as Juan de Betanzos and Pedro Cieza de León, who recorded oral traditions a century or more after the events. The outline of his career is broadly consistent across these sources, but its chronology is conventional rather than precise.

The traditions agree that Pachacuti, born Cusi Yupanqui, was a younger son of the ruler Viracocha Inca. When the rival Chanca people attacked Cusco, Viracocha and his designated heir Urco are said to have abandoned the city, while Cusi Yupanqui organized its defense and defeated the invaders. On the strength of this victory he displaced his father and brother and assumed rule, taking the name Pachacuti, commonly rendered as "he who overturns the world" or "earth-shaker."

His reign, in the chroniclers' telling, combined conquest with reorganization. Campaigns led by Pachacuti and later by his son Topa Inca Yupanqui extended Inca control across the central Andes, incorporating peoples by a mixture of warfare, negotiation, and resettlement. To him are attributed core institutions of the mature empire: the rebuilding of Cusco, including the Coricancha temple complex; the elaboration of the state cult of the sun god Inti; systems of labor obligation and population transfer; and the network of roads and storehouses that bound the provinces to the capital. Modern archaeology associates his reign with the royal estate at Machu Picchu, which scholars generally interpret as built for Pachacuti's lineage.

He died around 1471 and was succeeded by Topa Inca Yupanqui, who continued the expansion northward and along the coast. Pachacuti's descendants ruled until the Spanish conquest: his grandson Huayna Capac pushed the frontiers to their greatest extent, and the war between his great-grandsons Huáscar and Atahualpa divided the empire on the eve of Francisco Pizarro's arrival. Whatever allowance is made for the embellishments of dynastic memory, the imperial system the Spaniards encountered was largely credited by the Incas themselves to Pachacuti.