The posting below by Professor Fridrik Thordarson’s discussion on the linguistic contacts between Iran and the Caucasus was orginally published in the Encyclopedia Iranica.
Caucasian (or Ibero-Caucasian) languages is the designation of those languages of the area that do not belong to any other known family of languages. They fall into four distinct groups: a) the Kartvelian or South Caucasian languages: Georgian, Svan, and Mingrelian (mainly spoken in the Georgian S.S.R.), and Laz (mostly spoken in Turkey). b) The Northwest Caucasian languages: Abkhaz (in the Karachai-Cherkes A.O., R.S.F.S.R.), Adyge (West Circassian, in the Adyge A. O., R.S.F.S.R.), Kabardian (East Circassian, in the Kabard-Balkar A.S.S.R., R.S.F.S.R.), and Ubykh (in Turkey, now all but extinct). c) The North-central Caucasian (Nakh) languages: Ingush and Chechen (in Chechen-Ingush A.S.S.R., R.S.F.S.R.) and Bats (in the Georgian S.S.R). d) The Northeast (Dagestanian) languages: Avar, the various Andi, Dido, Lak-Dargva, and Lezgian languages (Dagestanian A.S.S.R., R.S.F.S.R., and the Azerbaijanian S.S.R.). Some scholars include the Nakh languages in the Northeast Caucasian group. Otherwise the genetic affinities between the four groups are uncertain.
a) Azeri (in the Azerbaijanian S.S.R and in northwestern Iran). b) Anatolian Turkish (in a few communities in Transcaucasia). c) Kumyk (mainly in Dagestanian A.S.S.R.). d) Nogay (in various places in north Caucasus). e) Karachai-Balkar (in the Karachai-Balkar A.S.S.R. and the Kabard-Balkar A.S.S.R.).
Indo-European languages (Armenian, Greek, Slavonic)
a) Armenian (mainly in the Armenian S.S.R., but also in the Georgian and Azerbaijanian S.S.R. and in various countries outside the Soviet Union). b) Greek (in the Georgian S.S.R. and in north Caucasus). c) Slavonic languages (Russian, Ukrainian, mainly in north Caucasus; Russian is also used as an administrative language all over the area, in part beside the indigenous languages). d) Various Iranian languages (see below).
The only Caucasian language with an old literary tradition is Georgian (texts since a.d. the 5th century); in some of the other languages literatures have arisen in modern times, mainly after the establishment of Soviet power. Today twelve of the Caucasian languages have status of literary languages: Georgian, Abkhaz, Abaza, Adyge, Kabard-Cherkes, Chechen, Ingush, Avar, Lak, Dargva, Lezgi, Tabasaran.
Christian literature in Caucasian Albanian (possibly a Lezgian language still surviving as Udi in northern Azerbaijan) is known to have existed in late Antiquity; it became extinct in the Middle Ages (Mnacakanjan; Schulze).
The Armenian literature dates back to a.d. the 5th century. The Greek and Slavic groups have no indigenous literature. For Iranian languages, see below. (For general surveys see Comrie and Hewitt; Deeters; Faensen; Yazyki narodov SSSR.)
Indo European Iranian Languages in the Caucasus
The following Iranian languages are spoken in the Caucasus and Transcaucasia (see Oranskij, Schmitt, in addition to the works referred to above): Kurdish (Kurmanji), in the Soviet republics of Armenia, Azerbaijan, and Georgia (ca. 75,000 speakers); Tati in southern Dagestan and northern Azerbaijan (ca. 10,000); Ṭāleši in Azerbaijan (ca. 10,000); and Ossetic (ca. 480,000) in the northern Caucasus and Georgia (South Ossetia; figures taken from the Soviet census of 1979, except that for Ṭāleši speakers, which is from 1959; see Faensen, pp. 103-04). Bilingualism (or multilingualism) is widespread, even the rule, in all these language communities. In Soviet Azerbaijan the majority of the Tati- and Ṭāleši-speaking populations also speak Azeri Turkish, which is the language of instruction and administration, and claim ethnic identification with Azeris; the census figures for these two languages may thus be too low. Ṭāleši is also spoken in Iranian Azerbaijan. Both Kurdish and Ossetic are written languages, with rich literatures. See also individual articles on Azeri (azerbaijan viii), Kurdish, Ossetic, Tati, and Ṭāleši, and cf. azerbaijan vii.
Kurdish. The Georgian Kurds, who live for the most part in the region of Tbilisi, are immigrants from Armenia, whereas the Kurds of Azerbaijan mainly occupy the territory along the Armenian border. The language of these communities is almost identical with that of the Armenian Kurds (see Bakaev, 1973, 1977).
Tati. Tati belongs to the group of so-called Southwest Iranian languages and is closely related to Persian (for bibliography see Oranskij, II) and should not be confused with the Tati dialects spoken in Azerbaijan, Zanjān and Qazvīn and which belong to the Northwest Iranian (see E. Yarshater, A Grammar of Southern Tati Dialects, The Hague and Paris, 1969). It is spoken by two main groups, one Jewish (Russ. gorskie evrei, mountain Jews), the other Muslim; there is also a small group of Christian Tati-speakers in Armenia. According to tradition, speakers of Tati are descended from military colonists of southwestern Iran who were settled in southern Dagestan in the Sasanian period (Yazyki narodov SSSR I, p. 281 ). For the Jews of this region Tati is also a literary language. Tati has drawn heavily upon the vocabulary of Azeri, the predominant language of the region. Even postpositions, conjunctions, and particles and derivational suffixes (e.g., -lik, -lýk, -lug, -lïq, primarily used to form abstract nouns; -či, denoting practitioner of a profession (Gryunberg, 1963, p. 19) have been borrowed. Numerous Arabic words, especially those relating to Islam, have also been adopted, partly through Azeri. Other borrowings include Persian words, either directly or through Azeri; modern Russian loanwords, usually in their Azeri form; and numerous words from the Northeast Caucasian (Lezgian) languages of southern Dagestan. Syntactic loans in the form of calques are frequent, but, despite the strong influence exerted by Azeri, Tati grammar remains predominantly Iranian. Azeri influence on the sound system manifests itself especially clearly in a tendency to introduce vowel harmony (Gryunberg, 1963, p. 11; in Yazyki narodov SSSR I, pp. 281-301; Oranskij, I, pp. 163-69; Sokolova, pp. 122-47).
Ṭāleši. Tāleši belongs to the group of so-called Northwest Iranian languages, which prevailed throughout Azerbaijan from antiquity to the later Middle Ages. Like Tati, Ṭāleši has borrowed extensively from Azeri. Paired Azeri and indigenous synonyms are common. Azeri suffixes like -lik (-li, -luk) and -či are found in derivations of Ṭāleši words. Azeri participles in -miš are used to form compound verbs (allatmiš karde “to deceive,” kečmiš be “to forgive”). In the 1930s an attempt was made to introduce a written form of Ṭāleši, but it was soon abandoned. (See Miller, in Yazyki narodov SSSR I, pp. 302-22; Sokolova, I, pp. 104-21.)
Ossetic. Ossetic is spoken in a comparatively small area in the central Caucasus flanked on all sides by Caucasian and Turkic-speaking areas. On the east it is bordered by the Nakh languages (Ingush, Chechen), on the west by Kabardian (Circassian) and Balkar (Turkic). In South Ossetia the bulk of the Ossetic population is bilingual in Ossetic and Georgian. Since the middle of the 18th century Russian has gradually spread through the northern Caucasus and must now be considered the predominant language of the area. There is evidence, however, that Ossetic (or its ancestor language, Alania, see alans) formerly had much greater currency, especially in the northwestern Caucasus, where in the Middle Ages it seems to have been a language of status. Iranian (Scythian, Sarmatian) languages have been spoken in southern Russia and the Ponto-Caspian steppes since at least as early as the first half of the 1st millennium b.c. It has even been maintained that the Scythians and Sarmatians may have been indigenous to those areas, the descendants of Aryan tribes who remained in their ancient habitat when the majority of their sister tribes migrated to the east and south (Abaev, 1965; Jettmar, pp. 62-64). Iranian cultural influence in the northern Caucasus was also apparently strong in former times. The epic cycle of the Narts, current in many parts of the northern Caucasus and in various languages, seems to be largely of Iranian origin (see Dumézil, tr., and 1968, pp. 441-575; Abaev, 1945; Nartị kaddżiṯä). The former spread of Ossetic (Alanic) is borne out by numerous place names in territories now occupied by Circassian (Kabardian) tribes: river names in -dan = Oss. don “water, river,” names of gorges or ravines in -kam = Oss. kom “mouth, gorge,” and so on. In these territories Ossetic has gradually been ousted by Turkic- and, in particular, Circassian-speaking tribes, who in the late Middle Ages began to spread north and east from the coasts of the Black Sea (Abaev, 1949, passim, and 1987; Gagloĭti; Kaloev; Istoriya Severo-osetinskoĭ ASSR I; see also Âčarkas). In the 16th and 17th centuries the feudal lords of Kabarda had hegemony over the northern Caucasus, and their language was predominant (Istoriya Severo-osentinskoĭ ASSR I, pp. 104-19). A number of lexical affinities between Ossetic and Circassian-Kabardian attest the close relations between the speakers of these languages (Abaev, 1949, I, p. 88 and passim; Thordarson, in Schmitt, ed.). Mutual borrowings have also taken place between Ossetic and Abkhas, Mingrelian, and Svan (Abaev, 1949, I, passim); today these language areas are separated from the Ossetic area by Turkic- and Circassian-speaking populations. On the other hand, there is some evidence that Ossetic is now spoken in territory that was formerly occupied by Nakh tribes: The oldest strata of the southern Ossetic-speaking population are descended from immigrants from the north who settled in the Java district around the upper reaches of the Didi Liaxvi river in the late Middle Ages or early modern times (Ocherki istorii I).
Today there are two chief dialects of Ossetic, Digor (West Ossetic) and Iron (East Ossetic). South Ossetic is a local variant of Iron but has been more strongly exposed than North Ossetic to lexical influence from Georgian (Abaev, 1949, I, pp. 494-506; Tedevi, 1983); plant names and other lexemes referring to local conditions in Transcaucasia are largely of Georgian origin (Tekhov, pp. 110-22 and passim). A number of lexical affinities that connect Digor and Kabardian are not shared by Iron. The population of the Ordzhonikidze area (eastern Ossetia) is partly bilingual in a Nakh dialect (Ingush) and Iron, which has resulted in a good deal of mutual lexical borrowing. Among Ossetic words that seem to have been adopted from Nakh at an early date are bäx “horse” (attested in the so-called “Yass word list,” written in Hungary in the 15th century but deriving from an Alanic colony established there in the 13th century; see Németh, 1959; Thordarson, in Schmitt, ed.) and läg “man” (a probable reading of the Alanic inscription from the Zelenchuk river, 11th-12th century; see Zgusta, 1987); the words for “hand,” “foot,” and “mouth” (I. kʾux/D. kʾox; kʾax; I. dzix/D. dzux; çʾux respectively), which have ousted the older words arm, fad, kom, may also have been borrowed from Nakh. All these words are common to both dialects.
Since Khazar times (a.d. 6th century) there have been language contacts between Ossetic (Alanic) and various Turkic tribes. The influence exerted by the Turkic languages upon Ossetic seems to have been much more profound than that of the Caucasian languages, at least as far as vocabulary is concerned. Turkic languages have apparently acted as intermediaries between Ossetic and Uralic and Altaic languages in southern Russia and Central Asia; quite a number of plant names seem to be migratory words that have entered the Caucasus from the north (see Tekhov). In the Zelenchuk inscription at least one Turkic proper name is attested (pakathar