The Chagatai Khanate was founded when Genghis Khan gave each of his four sons a territory to rule autonomously within the Mongol Empire. Genghis khan’s second son’s Chagatai Khanate embraced most of Kazakhstan, Uzbekistan and western Xinjiang, northern Afghanistan, Tajikstan. The historical administrative capital was Samarkand, a center for the camel caravans which crossed Asia. His state was thus surrounded by other three Mongol khanates: the Ilkhanate to the west, the Golden Horde to the north, and the Empire of the Great Khan (Yuan Dynasty Empire) to the east.
This Khanate was part of the Mongol Empire before Yuan Dynasty fell in the late 14th century. Then it later became fully independent. Tsagadai Khan ruled his kingdom from 1227 until his death in 1242. Chagatai had three sons Mutukan, Baidar and Yesü Möngke with his wife Ebuskun. However, Chagatai nominated his grandson Qara Hülëgü as his successor with Ebuskun acting as regent for the young man.
Although the western half of the khanate was lost to Tamerlane in the 1360s. The eastern half remained under Chagatai khans who were, at times, allied or at war with Timur’s successors.
The khanate lasted in one form to another from 1220s until the late 17th century.