Known as Turan to the Persians, western Turkestan has also been known historically as Sogdiana, "Ma wara'u'n-nahr" (by its Arab conquerors), and Transoxiana by Western travelers. The latter two names refer to its position beyond the River Oxus when approached from the south, emphasizing Turkestan's long-standing relationship with Iran, the Persian Empires, and the Umayyad and Abbasid Caliphates.
Oghuz Turks (also known as Turkmens), Uzbeks, Kazakhs, Khazars, Kyrgyz, Hazara and Uyghurs are some of the Turkic inhabitants of the region who, as history progressed, have spread further into Eurasia forming such Turkic nations as Turkey, and subnational regions like Tatarstan in Russia and Crimea in Ukraine. Tajiks and Russians form sizable non-Turkic minorities.
Of Persian origin (see -stan), the term "Turkestan" (?) has never referred to a single nation state. Iranian geographers first used the word to describe the place of Turkic peoples. "Turkestan" is used to describe any place where Turkic peoples lived.
On their way southward during the conquest of Central Asia in the 19th century, the Russians under Nikolai Aleksandrovich Veryovkin took the city of Turkistan (in present-day Kazakhstan) in 1864. Mistaking its name for the entire region, they adopted the name of "Turkestan" (Russian: ) for their new territory.
The history of Turkestan dates back to at least the third millennium BC. Many artifacts were produced in that period, with much trade being conducted. The region was a focal point for cultural diffusion, as the Silk Road traversed it.
Turkic sagas, such as the "Ergenekon" legend, and written sources, such as the Orkhon Inscriptions, state that Turkic peoples originated in the nearby Altai Mountains, and, through nomadic settlement, started their long journey westwards. Huns conquered the area after they conquered Kashgaria in the early 2nd century BC. With the dissolution of the Huns' Empire, Chinese rulers took over Eastern Turkestan. Arab forces captured it in the 8th century. The Persian Samanid dynasty subsequently conquered it and the area experienced economic success. The entire territory was held at various times by Turkic forces, such as the Göktürks, until the conquest by Genghis Khan and the Mongols in 1220. Genghis Khan gave the territory to his son Chagatai and the area became the Chagatai Khanate. Timur took over the western portion of Turkestan in 1369, and the area became part of the Timurid Empire. The eastern portion of Turkestan was also called Moghulistan and continued to be ruled by descendants of Genghis Khan.
In Chinese historiography, the Qara Khitai is most commonly called the "Western Liao" () and is considered to be a legitimate Chinese dynasty, as is the case for the Liao dynasty. The history of the Qara Khitai was included in the History of Liao (one of the Twenty-Four Histories), which was compiled officially during the Yuan dynasty by Toqto'a et al.
After the Tang dynasty, non-Han Chinese empires gained prestige by connecting themselves with China; the Khitan Gurkans used the title of "Chinese emperor", and the empire was also called the "Khan of Ch?n". The Qara Khitai used the "image of China" to legitimize their rule to the Central Asians. The Chinese emperor, together with the rulers of the Turks, Arabs, India, and the Byzantine Romans, was known to Islamic writers as the world's "five great kings". Qara Khitai kept the trappings of a Chinese state, such as Chinese coins, Chinese imperial titles, the Chinese writing system, tablets, seals, and used Chinese products like porcelein, mirrors, jade and other Chinese customs. The adherence to Liao Chinese traditions has been suggested as a reason why the Qara Khitai did not convert to Islam. Despite the Chinese trappings, there were comparatively few Han Chinese among the population of the Qara Khitai. These Han Chinese had lived in Kedun during the Liao dynasty, and in 1124 migrated with the Khitans under Yelü Dashi along with other people of Kedun, such as the Bohai, Jurchen, and Mongol tribes, as well as other Khitans in addition to the Xiao consort clan.
Qara Khitai's rule over the Muslim-majority Central Asia has the effect of reinforcing the view among some Muslim writers that Central Asia was linked to China even though the Tang dynasty had lost control of the region a few hundred years ago. Marwaz? wrote that Transoxiana was a former part of China, while Fakhr al-D?n Mub?rak Sh?h defined China as part of "Turkestan", and the cities of Bal?s?gh?n and Kashghar were considered part of China.
The association of Khitai with China meant that the most enduring trace of the Khitans' power is names that are derived from it, such as Cathay, the medieval Latin appellation for China. Names derived from Khitai are still in use, such as the Russian, Bulgarian, Uzbek and Mongolian names for China. However, the use of "Khitai" to mean "China" or "Chinese" by Turkic speakers within China, such as the Uyghurs, is considered pejorative by the Chinese authorities, who have tried to ban it.