The exiled Khitans who built a Central Asian empire and helped name Cathay
When the Jurchens toppled the Liao dynasty, a Khitan noble named Yelü Dashi led refugees west and founded a new empire in Central Asia. It ruled mostly Turkic and Iranian subjects through Chinese-style government, crushed a Seljuk army in 1141, and its people's name, Khitai, became medieval Europe's Cathay.
The Jurchen Jin dynasty conquered the Liao between 1114 and 1125. Dashi joined the last Liao emperor, Tianzuo, was captured by the Jin in 1123, and later got back to him; Tianzuo himself was taken in 1125. In 1124 Dashi headed northwest to the garrison of Kedun on the Orkhon River, won over its 20,000 troops and took the title gurkhan, universal khan. He pushed west, capturing the Karakhanid city of Balasaghun in modern Kyrgyzstan in 1134 and annexing Fergana and Tashkent in 1137.
The showdown came on 9 September 1141 on the Qatwan steppe north of Samarkand. The Seljuk sultan Ahmad Sanjar had marched to protect his Karakhanid vassal, but the Khitans surrounded his army and drove its centre into a wadi about 12 kilometres from the city. Sanjar barely escaped, his wife was captured, and all of Transoxiana passed to the Khitans. Sources disagree wildly on the numbers: Khitan strength is given as anywhere from 20,000 to 700,000.
The rulers never called themselves Qara Khitai or Western Liao. They styled the state the Great Liao, a legitimate continuation of the old dynasty, and Chinese and Muslim histories accepted it as a genuine Chinese dynasty. Qara Khitai, usually rendered Black Khitans, seems to arise after the Mongol invasions from Turko-Mongol speakers mishearing the word for Liao as qara, black. Because Central Asians saw the Khitans as Chinese, Khitai came to mean China, reaching Europe as Cathay; related words still name China in Russian, Bulgarian, Uyghur and Kazakh.
The empire's reach touched parts of today's China, Kazakhstan, Kyrgyzstan, Mongolia, Tajikistan and Uzbekistan, with vassals such as the Kingdom of Qocho and the Kara-Khanid Khanate. It was usurped in 1211 by the Naiman prince Kuchlug, and the state fell to the Mongols in 1218. Some western Khitans went on to found the Qutlugh-Khanid dynasty in southern Iran.
Source: Qara Khitai
