Central Asia is a region of Asia bounded by the Caspian Sea to the southwest, European Russia to the northwest, China and Mongolia to the east, Afghanistan and Iran to the south, and Siberia to the north. It includes Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, and Uzbekistan. The countries as a group are also colloquially referred to as the "-stans" as all have names ending with the Persian suffix "-stan" (meaning 'land') in both respective native languages and most other languages.
In the pre-Islamic and early Islamic eras (c. 1000 and earlier) Central Asia was inhabited predominantly by Iranian peoples, populated by Eastern Iranian-speaking Bactrians, Sogdians, Chorasmians, and the semi-nomadic Scythians and Dahae. As the result of Turkic migration, Central Asia also became the homeland for the Kazakhs, Kyrgyzs, Tatars, Turkmens, Uyghurs, and Uzbeks; Turkic languages largely replaced the Iranian languages spoken in the area, with the exception of Tajikistan and areas where Tajik is spoken.
The Silk Road trade routes crossed through Central Asia, leading to the rise of prosperous trade cities. acting as a crossroads for the movement of people, goods, and ideas between Europe and the Far East. Most countries in Central Asia are still integral to parts of the world economy.
From the mid-19th century until near the end of the 20th century, Central Asia was colonised by the Russians, and incorporated into the Russian Empire, and later the Soviet Union, which led to Russians and other Slavs migrating into the area. Modern-day Central Asia is home to a large population of European settlers, who mostly live in Kazakhstan: 7 million Russians, 500,000 Ukrainians, and about 170,000 Germans. During the Stalinist period, the forced deportation of Koreans in the Soviet Union resulted in a population of over 300,000 Koreans in the region.
Central Asia has a population of about 72 million, in five countries: Kazakhstan (19 million), Kyrgyzstan (7 million), Tajikistan (10 million), Turkmenistan (6 million), and Uzbekistan (35 million).