The Caucasian languages comprise a large and extremely varied array of languages spoken by more than ten million people in and around the Caucasus Mountains, which lie between the Black Sea and the Caspian Sea. Linguistic comparison allows the classification of these languages into several different language families, with little or no discernible affinity to each other. However, the languages of the Caucasus are sometimes mistakenly referred to as a family of languages.
Families indigenous to the Caucasus
Three of these families have no current indigenous members outside the Caucasus, and are considered indigenous to the area. The term Caucasian languages is generally restricted to these families, which are spoken by about 11.2 million people.
Northeast Caucasian, also called the Nakh-Daghestanian or Caspian family, with a total of about 3.8 million speakers. Includes the Chechen language with 1.5 million speakers, the Avar language with 1 million speakers, the Ingush language with 500,000 speakers, the Lezgian language with 800,000 speakers, and others.
Northwest Caucasian, also called the Abkhazo-Adyghean, Circassian, or Pontic family, with a total of about 2.5 million speakers. Includes the Kabardian language, with one million speakers.
It is commonly believed that all Caucasian languages have many consonants. While this is certainly true for most members of the Northeast and Northwest Caucasian families, the consonant inventories of the South Caucasian languages are not nearly as extensive, ranging from 28 to 30 – comparable to languages like Russian, Arabic, and Western European languages. The autochthonous languages of the Caucasus share some areal features, such as the presence of ejective consonants and a highly agglutinative structure, and, with the sole exception of Mingrelian, all of them exhibit a greater or lesser degree of ergativity. Many of these features are shared with other languages that have been in the Caucasus for a long time, such as Ossetian.
External relations
Since the birth of comparative linguistics in the 19th century, the riddle of the apparently isolated Caucasian language families has attracted the attention of many scholars, who have endeavored to relate them to each other or to languages outside the Caucasus region. The most promising proposals are connections between the Northeast and Northwest Caucasian families and each other or with languages formerly spoken in Anatolia and northern Mesopotamia.
Linguists such as Sergei Starostin see the Northeast and Northwest families as related and propose uniting them in a single North Caucasian family, sometimes called Caucasic or simply Caucasian. This theory excludes the South Caucasian languages, thereby proposing two indigenous language families. While these two families share many similarities, their morphological structure, with many morphemes consisting of a single consonant, make comparison between them unusually difficult, and it has not been possible to establish a genetic relationship with any certainty.
Ibero-Caucasian languages
There are no known affinities between the South Caucasian and North Caucasian families. Nevertheless, some scholars have proposed the single name Ibero-Caucasian for all the Caucasian language families, North and South, in an attempt to unify the Caucasian languages under one family.
Hattic
Some linguists have claimed affinities between the Northwest Caucasian family and the extinct Hattic language of central Anatolia. See the article on Northwest Caucasian languages for details.
Alarodian
Alarodian is a proposed connection between Northeast Caucasian and the extinct Hurro-Urartian languages of Anatolia.
Linguists such as Sergei Starostin have proposed a Dené–Caucasian macrofamily, which includes the North Caucasian languages together with Basque, Burushaski, Na-Dené, Sino-Tibetan, and Yeniseian. This proposal is rejected by most linguists.
Families with wider distribution
Other languages historically and currently spoken in the Caucasus area can be placed into families with a much wider geographical distribution.