Caucasians who speak languages which have long been indigenous to the region are generally classified into three groups: Kartvelian peoples, Northeast Caucasian peoples and Northwest Caucasian peoples.
Northwest Caucasian languages
The largest peoples speaking languages which belong to the Caucasian language families and who are currently resident in the Caucasus are the Georgians (7,000,000), the Chechens (1,500,000 (according to 2010 Russian Census)), the Lezgins (about 800,000 (source Lezgins)), the Kabardins (600,000) and the Avars (500,000), while outside the Caucasus, the largest people of Caucasian origin, in diaspora in more than 40 countries (such as Jordan, Turkey, the countries of Europe, Syria, United States) are the Circassians with about 3,000,000-4,000,000 speakers. Georgians are the only Caucasian people who have their own undisputedly independent state--Georgia. Abkhazia's status is disputed. Other Caucasian peoples have republics within the Russian Federation: Adyghe (Adygea), Cherkess (Karachay-Cherkessia), Kabardins (Kabardino-Balkaria), Ingush (Ingushetia), Chechens (Chechnya), while other Northeast Caucasian peoples mostly live in Dagestan.
Caucasians that speak languages that belong to the Indo-European language family:
Armenians number 3,215,800 in their native Armenia, though approximately 8 million live outside the republic, forming the Armenian diaspora. Elsewhere in the region, they reside in Nagorno-Karabakh (which is de facto independent republic, though not recognized internationally), Georgia (primarily Samtskhe-Javakheti, Tbilisi, and Abkhazia), and the Russian North Caucasus. The Ossetians live in North Ossetia-Alania (autonomous republic within Russia) and in South Ossetia, which is de facto independent, but de jure is part of Georgia. The Yazidis reside in the western areas of Armenia, mostly in the Aragatsotn marz, and in the eastern areas of Georgia. An autonomous Kurdish region was created in 1923 in Soviet Azerbaijan but was later abolished in 1929. Pontic Greeks reside in Armenia (Lori Province, especially in Alaverdi) and Georgia (Kvemo Kartli, Adjara, the Tsalka, and Abkhazia). Pontic Greeks had also made up a significant component of the southern Caucasus region acquired from the Ottoman Turkish Empire (following the 1878 Treaty of San Stefano) that centred on the town of Kars (ceded back to Turkey in 1916). Russians mostly live in the Russian North Caucasus and their largest concentration is in Stavropol Krai, Krasnodar Krai, and in Adygea. Georgia and the former south Russian Caucasus province of Kars Oblast was also home to a significant minority of ethnic (Swabian) Germans, although their numbers have become depleted as a result of deportations (to Kazakhstan following WWII), immigration to Germany, and assimilation into indigenous communities.
Caucasians that speak languages that belong to the Semitic language family
Caucasians that speak languages that belong to the Turkic language family:
The largest of the Turkic-speaking peoples in the Caucasus are Azerbaijanis who number 8,700,000 in the Republic of Azerbaijan. In the Caucasus region, they live in Georgia, Russia (Dagestan), Turkey and previously in Armenia (before 1990). The total number of Azerbaijanis is around 35 million (25 million in Iran). Other Turkic speakers live in their autonomous republics within Russian Federation: Karachays (Karachay-Cherkessia), Balkars (Kabardino-Balkaria), while Kumyks and Nogais live in Dagestan.
This gives ethnic locations about 1775 before the Russians came. NWCLS means Northwest Caucasian Language speakers and NECLS means Northeast Caucasian Language speakers. The linguistic nationalities that we now recognize are somewhat artificial. Two hundred years ago a man's loyalty was to his friends, kin, village and chief and not primarily to his language group. The difference between steppe, mountain and plain was far more important than difference of language. Only the southern half (and the southernmost part of Dagestan) had organized states, usually Persian or Turkish vassals and few, if any, of these states corresponded well to language groups.
Northern Lowlands: The Turkic-speaking Nogai nomads occupied almost all of the steppe north of the Caucasus. In the nineteenth century they were pushed far southeast to their present location. Formerly part of the eastern steppe was occupied by Kalmyks - Buddhist Mongols who migrated from Dzungaria about 1618. In 1771 many returned to their original homeland and they contracted to their present location in the far northeast, Nogais temporarily taking their place. In the southeast were the isolated Terek Cossacks. Their settlements later grew into the North Caucasus Line. There were a few Turkmens in the center of the steppe.
North Slope: The western two thirds was occupied by Circassians - NWCLS divided into twelve or so tribes. They long resisted the Russians and in 1864 several hundred thousand of them were expelled to the Ottoman Empire. To their east were the Kabardians - NWCLS similar to the Circassians but with a different political organization. The term Lesser Kabardia refers to the eastern area. South of the eastern Circassian-Kabardians were three groups that seem to have been driven into the high mountains about 500 years previously. The Karachays and Balkars spoke similar Turkic languages. East of the Balkars were the Ossets - Iranian speakers descended from the ancient Alans who controlled the future Georgian Military Highway and had a growing Christian minority. East of the future highway was a north-south band of Ingush - NECLS similar to the Chechens. The numerous Chechens to the east were later to wage the long Murid War against the Russians. For the small groups south of the Ingush-Chechens see South Slope below. To the east along the coast were the Turkic Kumyks.
Mountain Dagestan: All the peoples of mountain Dagestan were NECLS except the Tats. In the northwest were a number of small language groups (Tsez people (Dido) and Andi people), similar to the Avars. To their southeast were the numerous Avars with a khanate at Khunzakh who fought in the Murid War. Southeast were the Dargwa people and west of them the Laks who held the Kumukh Khanate. Southeast along the Samur River were the Lezgian people with many subgroups and then the Iranian-speaking Tats down to Baku.
Caspian Coast: From Astrakhan to the Terek River there were the Buddhist Kalmykh nomads. Along the Terek were the isolated Terek Cossacks. From the Terek to Derbent were the Turkic-speaking Kumyks with a state at Tarki. The town of Derbent itself had a majority Persian (Russian: ) population, as it had for many centuries, until the late 19th century. On the coastal plain south of Derbent was a mixed population, mostly Azeri ("Transcaucasian Tatar"), and further south to Baku were the Iranian-speaking Tats. When Baku became a boom town the Tats retained a majority only in the mountains. The Mountain Jews, who had a number of villages inland from the coast, spoke a form of Tat called Judeo-Tat. The lowlands south of Baku were held by Azeris, Turkic-speaking Shiites. On both sides of the current Iranian border were the Iranian-speaking Talysh. Based on genetic studies the Gilaki and Mazanderani ethnic groups in northern Iran (near the Caspian Sea) have been proven to be genetically similar to Armenians, Georgians and Azeris. This indicates that the Gilaki and Mazanderani ethnic groups are people that immigrated from the Caucasus region to what is now northern Iran.
South Slope: Black Sea coast: In the northwest the mountains came down to the sea and the population was Circassian. Southward the coastal plain broadened and the population was Abkhazian - similar to the Circassians but under Georgian influence.
South Slope proper: On the south side of the Caucasus the mountains fall quickly to the plains and there is only a small transition zone. The inhabitants were either Georgians with mountain customs or northern mountaineers who had moved south. The Svans were Georgian mountaineers. In the center the Iranian Ossets had moved south and were surrounded on three sides by Georgians. East of the Ossets and south of the Ingush-Chechens were three groups of Georgian mountaineers on both sides of the mountain crest: Khevi, Khevsurs, and Tushetians. The Bats were NECLS entangled with the Tushetians and the Kists were Chechens south of the mountains. Near the Georgian-Azeri linguistic border there were some Avars and Tsakhurs (Lezgians) who had crossed the mountains. Associated with the Tsakhurs were the Ingiloy or Georgian-speaking Muslims. In the north Azeri area were a few Udins or southern Lezgians and Lakhij or southern Tats.
Southern Lowlands: The western two thirds were occupied by Georgians - an ancient Christian people with a unique language. The eastern third was Azeri - a group of Turkic-speaking Shiites under Persian influence. On the fringe of the Georgian area were Georgian speakers who had either adopted Islam or mountain customs.
Further South the land becomes higher. In the west were the Laz people or Georgian Muslims. In Kars province there were Turks, Kurds and Armenians. The Armenians were somewhat concentrated in modern Armenia but were mostly spread out as a minority all over Asia Minor. There were groups of Azeris west of their main area who tended to blend with the Turks. The Kurds were semi-nomadic shepherds with small groups in various places and concentrations in Kars province and Nakhchivan. In the far southeast were the Iranian Talysh.
Language groups in the Caucasus are closely correlated to genetic ancestry.
Chechen family from 1920
Pontic Greek militia fighters from the Transcaucasus region
Mountain Jews, c. 1898
Azerbaijani female from Baku (1897)
Khevsur clansmen in Georgia, c. 1910
Group of Lezgi men, 1880
Mullahs at the Mosque near Batumi, c. 1910
A raid by Kurdish
Groom wearing a chokha at a Tushetian wedding