Demographics of Central Asia



The nations which make up Central Asia are five of the former Soviet republics: Kazakhstan, Kyrgyzstan, Turkmenistan, Tajikistan and Uzbekistan, which have a total population of about million. Afghanistan is not always considered part of the region, but when it is, Central Asia has a total population of about 122 million (2016); Mongolia and Xinjiang (part of China) is also sometimes considered part of Central Asia due to its Central Asian cultural ties and traditions, although geographically it is East Asian. Most central Asians belong to religions which were introduced to the area within the last 1,500 years, such as Sunni Islam, Shia Islam, Ismaili Islam, Tengriism and Syriac Christianity (mostly East Syriac). Buddhism, however, was introduced to Central Asia over 2,200 years ago, and Zoroastrianism, over 2,500 years ago.

Ethnic groups
The below are demographic data on the ethnic groups in Central Asia

Genetic history
An analysis of Scytho-Siberian matrilineal DNA lineages of Iron Age human remains from the Altai region found evidence of a mixture of West Eurasian and East Asian maternal lineages. Prior to the Iron Age, all ancient maternal lineages in the Altai region were of West Eurasian origin, however Iron Age specimens show that Western Eurasian lineages were reduced by 50%, and East Asian lineages increased by 50%. The authors suggested that the rise of East Asian mtDNA lineages likely happened within the Iron Age Scythian period.

The ancestry of modern Central Asian populations is significantly derived from later Indo-Iranian and Turkic populations. A genetic study published in Nature in May 2018 examined the remains of four elite Türk soldiers buried between ca. 300 AD and 700 AD. 50% of the samples of Y-DNA belonged to the West Eurasian haplogroup R1, while the other 50% belonged to East Eurasian haplogroups Q and O. The extracted samples of mtDNA belonged mainly to East Eurasian haplogroups C4b1, A14 and A15c, while one specimen carried the West Eurasian haplogroup H2a. The authors suggested that central Asian nomadic populations may have been Turkicized by an East Asian minority elite, resulting in a small but detectable increase in East Asian ancestry. However, these authors also found that Türkic period individuals were extremely genetically diverse, with some individuals being of near complete West Eurasian descent. To explain this diversity of ancestry, they propose that there were also incoming West Eurasians moving eastward on the Eurasian steppe during the Türkic period, resulting in admixture.

A 2020 study analyzed genetic data from 7 early medieval Türk skeletal remains from Eastern Turkic Khaganate burial sites in Mongolia. The authors described the Türk samples as highly diverse, carrying on average 40% West Eurasian, and 60% East Eurasian ancestry. West Eurasian ancestry in the Türks combined Sarmatian-related and BMAC ancestry, while the East Eurasian ancestry was related to Ancient Northeast Asians. The authors also observed that the Western Steppe Herder ancestry in the Türks was largely inherited from male ancestors, which also corresponds with the marked increase of paternal haplogroups such as R and J during the Türkic period in Mongolia. Admixture between East and West Eurasian ancestors of the Türkic samples was dated to 500 CE, or roughly 8 generations prior. Three of the Türkic-affiliated males carried the paternal haplogroups J2a and J1a, two carried haplogroup C-F3830, and one carried R1a-Z93. The analyzed maternal haplogroups were identified as D4, D2, B4, C4, H1 and U7.

Mongolians and Kazakhs derive most of their ancestry from Ancient Northeast Asians (60–94%), with a variable amount of West Eurasian admixture (6–40%) from a Bronze Age Western Steppe Herder source. pp. 5-11: "Chinese Kazakhs shared significant more alleles with West Eurasians than any other Mongolian groups. We here confirm the genetic  substructure within three Mongolian groups and Chinese Kazakhs was caused by the different  amounts of West Eurasian related admixture in them." "We showed that there are genetic substructures within Mongolians corresponding to Ölöd, Chahar, and Inner Mongolian clusters, which is consistent with their tribe classifications. The substructure is shaped by the relatedness of Mongolians to West Eurasians. Mongolians and Kazakhs are on a genetic cline in terms of different proportions of West Eurasian related admixture from 6% to 40%. The genetic source for the West Eurasian ancestry was most likely Bronze Age Steppe population-related. We note that the small number of sampled individuals from different tribes is a limitation of the study. However, our findings are consistent with archaeological and ancient genomic evidence that the Bronze Age Steppe populations shaped the culture and genetic makeup of northern Eurasia through rapid expansion (Allentoft et al., 2015)." Similarly, the Kyrgyz people derive a significant part of their ancestry from East Asian-related populations (c. 59.3–69.8%), as well as from Iranian-related sources. Modern Iranian-speaking Central Asians (Tajiks), in contrast to Turkic-speaking Central Asians, have less Northeast Asian ancestry (7.7–18.6%), but harbor another East Eurasian component (8%) associated with indigenous South Asians (represented by Andamanese peoples). Uzbeks can be modeled as 48.8–65.1% Iron Age Indo-Iranians, and 34.9–51.2% Eastern Steppe Xiongnu, from the Mongolian Plateau, or as 40-55% Eastern Asian and 45-60% European/West Asian. Ancestry related to one of the earliest inhabitants, particularly the Ancient North Eurasians, is still found in low amounts among modern-day Central Asians.

A 2022 study confirmed the genetic continuity between modern Indo-Iranian-speaking Central Asians and Iron Age populations in southern Central Asia. Iron Age Central Asians were descended from historical Indo-Iranians, who settled in the region at the end of the Bronze Age. By the end of the Iron Age, East Asian ancestry was introduced via historical Turko-Mongol groups, but that type of ancestry remained low among remaining Indo-Iranian-speakers, while it makes up to 50% among modern Turkic-speaking Central Asians in northern Central Asia.