Encyclopedia of the Incas

Quechua became the official language of the Inca Empire under the last Inca
rulers, Topa Inca Yupanqui and Huayna Capac. There is speculation that one of
the main reasons why the Incas might not only have changed languages, but also
have seen the strategic need to make it the official language of the empire, might
have been that it was used, although in different dialects, throughout
Chinchaysuyu, either as the only language or as the most prestigious one in
places where it competed with others.
The form of Quechua adopted by the Incas became extinct after the Spanish
conquest. It appears indirectly in the earliest chronicles, reflected in the Incas’
cultural and institutional lexicon, and in the sporadic recording of phrases and
expressions. It also appears in the earliest grammatical and lexical treatise,
which was written by the Dominican friar Domingo de Santo Tomás of Seville in
1550 and published in Valladolid, Spain, in 1560. Compared with current
varieties of the language, the Quechua of the Incas had notable exclusive
phonological and lexical characteristics, although its grammar did not differ
much from modern dialects of what is known as “southern Quechua,”
particularly the form spoken in Ayacucho. Once recognized as the official
language, it had to compete with other languages that had existed since before
the expansion of the Inca Empire (Aymara and Culli in the south-central and
northern highlands, respectively, but also with native languages in Ecuador’s
inter-Andean valleys)—unless it was imposed in territories conquered by the last
Inca rulers (in Cochabamba, Bolivia, for example). In many places, such as on
Peru’s northern coast, however, it did not have time to become well established
before the sudden collapse of the empire.
Such was the “general language” to which the chroniclers refer—particularly
Santo Tomás, in his Dedicatoria al Rey (Dedication to the King), who describes
Quechua as a “tongue that was used and is used throughout the dominion of the
great ruler known as Guaynacapa [Huayna Capac], which covers an area that is
more than one thousand leagues in length and more than one hundred in breadth.
In all of that [land] it was generally used by the leaders and most important
people and by a large number of the common folk” (1995 [1560]). This common
variety, disseminated by the Incas throughout Tahuantinsuyu, was celebrated by
the conquistadors because of its extraordinary functionality for widespread
communication, despite the linguistic diversity and many dialects of the empire.
It would die out by the second half of the sixteenth century, succumbing to
Spanish in Lima and the surrounding areas, and to the languages of peoples
recently incorporated into the empire or to dialects of the same family (such as