Mongol invasion of Central Asia The Mongol invasion of Central Asia occurred after the unification of the Mongol and Turkic tribes on the Mongolian plateau in 1206 . It finally completed when Genghis Khan conquered the Khwarizmian Empire in 1221 . The Uyghurs , Qarluqs and Khara - Khitan Khanate . The Uyghurs , Qarluqs and local Turkic and Tajik peoples submitted to the Mongolians . The Uyghur state of Kara - Khoja was a vassal of the Kara - Khitans , but in 1210 , the Uyghur ruler of Kara - Khoja , Idiqut Barchuq appeared before the Khan to declare his allegiance to the Mongolians . He was rewarded with the daughter of Genghis in marriage , and the Uyghurs served under the Mongols as bureaucrats . A leader of the Qarluq and Buzar , the warlord of Chuy Valley , followed the Uyghur example . The Kara - Khitans ( Black Khitan ) were Khitans of the Liao Dynasty ( 907 – 1125 ) who were driven out from China by the Jurchens of the Jin Dynasty . In 1124 some Khitans moved westward under Yeh - lü Ta - shih ’ s leadership and created the Kara - Khitan Khanate ( Western Liao ) between in the Semirechye and the Chu River . They dominated Central Asia in the 12th century afer they defeated the Great Seljuk leader Ahmed Sanjar at the Battle of Qatwan in 1141 . However , their power was shattered in 1211 through the combined actions of the Khwārezm - Shah ʿAlāʾ ad - Dīn Muḥammad ( 1200 – 20 ) , and Küchlüg , a fugitive Naiman prince in flight from Chinggis Khaan ’ s Mongolians . Kuchlug was given shelter by the Kara - Khiitans , but he usurped the Gurkhan ' s throne in 1211 . Kuchlug attacked the city of Almaliq , and the Qarlugs there who were vassal of the Mongolians appealed to Chinggis Khaan for help . In 1216 , Genghis dispatched his general Jebe to pursue Kuchlug . The Mongols defeated the Kara - Khitans at Balasaghun , Kuchlug fled , but was later killed in 1218 . Khwarezmia . The Mongol invasion of Khwarezmia lasted from 1219 to 1221 . In fact , it was not originally the intention of the Mongol Empire to invade the Khwarezmid Empire . According to Juvaini , Genghis Khan had originally sent the ruler of the Khwarezmid Empire , Sultan Muhammad Aladdin , a message greeting him as his equal : " We now have the obligations of neighbors . Human wisdom requires that both sides walk the path of concord and observe the duties of friendship . " The Mongols ' original conquest of all " people in felt tents " , unifying the nomadic tribes in Mongolia and then the Turcomen s and other nomadic peoples , had come with relatively little bloodshed , and almost no material loss . However , the Governor of Otrar refused to receive the mission and had all 450 of them killed with permission from the Sultan . Upon hearing of this atrocity months later , Genghis Khan flew into a rage and used the incident as a pretext for invasion . The Mongol invasion of Central Asia however would entail the utter destruction of the Khwarezmid Empire along with the massacre of much of the civilian population of the region . According to Juvaini , the Mongols ordered only one round of slaughter in Khwarezm and Transoxiana , but systematically exterminated a particularly large portion of the people of the cities of Khorasan . This earned the Mongols a reputation for bloodthirsty ferocity that would mark the remainder of their campaigns . During the invasion of Transoxania in 1219 , along with the main Mongol force , Genghis Khan used a Chinese specialist catapult unit in battle . They were used again in 1220 in Transoxania . The Chinese may have used the catapults to hurl gunpowder bombs , since they already had them by this time While Genghis Khan was conquering Transoxania and Persia , several Chinese who were familiar with gunpowder were serving with Genghis ' s army . Historians have suggested that the Mongol invasion had brought Chinese gunpowder weapons to Central Asia . One of these was the huochong , a Chinese mortar .