The story of Quechuan
01
From One 'General Language' to a Family
For most of its written history Quechua was treated as a single language. Spanish grammarians of the 16th and 17th centuries, from Domingo de Santo Tomás (1560) to Diego González Holguín (1607), described one 'general language of Peru' and regarded the speech of other valleys as local corruptions of it. Travellers and priests knew perfectly well that a Cusco speaker struggled to follow the Quechua of Ancash, but the difference was put down to rustic usage rather than history.
The modern picture came from fieldwork in the central highlands in the early 1960s. Working independently, Gary Parker (1963) and Alfredo Torero (1964) compared the varieties systematically, sound by sound and suffix by suffix, and both found the same deep division: a central block, which Torero called Quechua I and Parker Quechua B, against everything to the north and south of it, Torero's Quechua II. The evidence was a bundle of shared innovations rather than scattered resemblances: the way the first person is marked, the shape of several verbal suffixes, and sound changes that each group had undergone and the other had not.
That work changed the question from 'which dialect is correct?' to 'what did the ancestor look like?', and reconstruction of Proto-Quechua followed, notably by Parker and Rodolfo Cerrón-Palomino (1987). Whether to call the result one language with many dialects or a family of languages is partly a matter of definition. Speakers from the two ends of the range cannot readily understand each other, and catalogues such as Ethnologue and Glottolog now list several dozen separate Quechua languages, while many speakers and national governments still speak of 'Quechua' in the singular.
02
Out of Central Peru
Linguists place the Quechua homeland in central Peru for one main reason: that is where the family is most diverse. The Quechua I varieties of Ancash, Huánuco, Pasco and Junín differ more among themselves than all the Quechua II varieties spread across three thousand kilometres from Colombia to Argentina. By the same reasoning that locates English's ancestors around the North Sea, the long-settled core is the centre and the uniform periphery is the product of later spread. Torero thought the ancestor was spoken on the central coast and adjacent highlands, perhaps around the valleys inland from modern Lima.
The spread came in stages. An early split separated Quechua I from Quechua II, probably during the first millennium CE, although no date is secure; figures from lexicostatistics are no longer trusted. Quechua II then moved outward, and Torero argued that the coastal trading lordship of Chincha carried it along sea routes to the north before the Inca. Other scholars, including Paul Heggarty and David Beresford-Jones, have tried to match stages of Quechua expansion with archaeological horizons such as the Wari state (c. 600–1000 CE). These alignments are plausible but unproven, because pottery and buildings do not reveal what language their makers spoke.
The last and best documented stage is the Inca one. From the 15th century the Inca used a southern Quechua II variety to administer an empire stretching from Ecuador to Chile, and Spanish missionaries and officials kept it in use afterwards. This explains why Quechua reached Ecuador, Bolivia and Argentina so recently and why those regions show so little internal diversity. Genetic studies of Andean populations exist, but they have not yet resolved when or how the language moved relative to people.
03
Suffixes, Evidence and Three Vowels
Quechua languages are easy to recognise once you know what to listen for. The inherited sound system has only three vowels, a i u, which are pronounced lower, as [e] and [o], next to the uvular stop q, a sound made further back in the mouth than English k. There are no inherited voiced stops such as b, d, g; words containing them are usually loans from Spanish. Stress falls regularly on the second-to-last syllable.
Grammar works almost entirely by adding suffixes, one after another, each with a single job. Cusco wasiykunapi is wasi-y-kuna-pi, 'house-my-plural-in', 'in my houses'. There are no prefixes at all. The usual order in a sentence is subject, object, verb, and modifiers come before what they modify. Verbs agree with both subject and object, and several persons of 'we' are distinguished: Cusco ñuqanchik 'we, including you' against ñuqayku 'we, not including you'.
The feature that most interests linguists is evidentiality. A speaker attaches a small suffix to a sentence to say how they know it. In Cusco Quechua, paranmi 'it is raining' uses -mi for something the speaker has witnessed or is sure of, while paransi uses -si, 'it is raining, so I am told', and -chá marks a guess. Aymara, the family's long-standing neighbour, has a similar system, and the two share much of their phonology and structure.
The Andes had no pre-Columbian script in the usual sense. The Inca recorded information on knotted cords, khipu, and whether any of these encoded language rather than numbers is still being studied. Quechua has been written in the Latin alphabet since the 16th century, with long-running disputes over spelling, including whether to write three vowels or five.
04
What Is Still Argued Over
The sharpest debate concerns Aymara. Quechua and the Aymaran languages share a large part of their vocabulary, a nearly identical inventory of consonants and a similar suffixing grammar. Some linguists, among them the proponents of a 'Quechumaran' stock such as Carolyn Orr and Robert Longacre (1968), have taken this as evidence of common descent. Most specialists, including Willem Adelaar, conclude that the resemblances come from a millennium or more of close contact and bilingualism, since the shared words lack the regular sound correspondences that inherited vocabulary should show. Neither side has produced a decisive test, because intense early contact could erase the difference between loans and cognates.
The internal tree is also less settled than the neat I-versus-II division suggests. Torero's Quechua II-A, including Cajamarca and Cañaris-Incahuasi, shares features with both main groups, and its place is disputed. Some scholars argue that Quechua behaves more like a dialect continuum, with innovations spreading across overlapping areas, than like a family tree with clean splits. The dating of Proto-Quechua is similarly open: most estimates fall in the first millennium CE, but some would put it earlier, and none rests on firm calibration.
Outside the Andes, no link has been demonstrated. Joseph Greenberg placed Quechua in a broad 'Andean' group within his Amerind hypothesis, but that grouping rests on loose resemblances across huge areas and is not accepted by most Americanists. For now Quechuan is best treated as an independent family, with Aymaran its closest partner by contact, and possibly more.