The Inca-Chanka war was a semi-legendary,[1] mytho-historical,[2] potentially mythical,[3] military conflict fought between Cusco and the Chanka chiefdom, several generations prior to the arrival of Europeans.

Because of his victory, Cusi Yupanqui, whose later name was Pachacuti, gained universal recognition, overthrowing his father, the ruler of Cusco, and his brother Urco, the co-ruler and designated heir.

[6] The effects of the war were exaggerated by the Inca ruling class, which made Cusi Yupanqui the archetype of its philosophical principals.

[7] The historical accuracy of the story told by colonial documents of the episode of the chanka attack against Cusco is regularly questioned.

[1] According to the archaeologist and anthropologist Gary Urton, two historiographical traditions exist; one considers Spanish colonial sources reliable and supports that the Chanka attack on Cusco represented the moment Inca myth became history, while the other thinks that the Chanka-Inca War was semi-legendary, but contained historical details, including the occupation of former Wari lands.

[2] Since the early 1980s, following the publication of a paper by the French anthropologist Pierre Duviols, the academic consensus has seen the war as a largely mythical event.

[9] Franck Garcia indicates that archeological research in the Andahuaylas region supports the existence of a powerful polity,[7] while for Franck Meddens and Cirilo Vivanco Pomacanchari, the chanka confederation was a loose defensive alliance of various independent local chiefdoms, while the Inca chiefdom of Cusco had a ruling elite, a unified cultural identity, and was in the process of developing a state structure.

[3] For Luis Millones and Brian Bauer, the war was a "legendary saga" conceived to explain Inca ascension to power, which would have been of part of ancient Wari tradition.

[22] Once Viracocha Inca and his son, Urco, who he had named co-ruler, heard of the Chanka attack, they fled Cusco together with their court.