According to the Sima Qian's Shiji, the nomadic Indo-European Yuezhi originally lived between Tengri Tagh (Tian Shan) and Dunhuang in Gansu, China. However, the Yuezhi were assaulted and forced to flee from the Hexi Corridor of Gansu by the forces of the Xiongnu ruler Modu Chanyu, who conquered the area in 177–176 BC (decades before the Han Chinese conquest and colonization of western tip of Gansu or the establishment of the Protectorate of the Western Regions). In turn the Yuezi attacked and pushing the Sai (i.e. Saka) west into Sogdiana, where in the mid-2nd century BC the latter crossed the Syr Darya into Bactria, but also into the Fergana Valley where they settled in Dayuan, south towards northern India, and eastward as well, where they settled in some of the oasis city-states of the Tarim Basin. Whereas the Yuezhi continued westward and conquered Daxia around 177–176 BC, the Sai (i.e. Saka), including some allied Tocharian peoples, fled south to the Pamirs before heading back east to settle in Tarim Basin sites like Yanqi (焉耆, Karasahr) and Qiuci (龜茲, Kucha). The Saka are recorded as inhabiting Khotan by at least the 3rd century and also settled in nearby Shache (莎車), a town named after its Saka inhabitants (i.e. saγlâ). Although the ancient Chinese called Khotan Yutian (于闐), its more native Iranian names during the Han period were Jusadanna (瞿薩旦那), derived from Indo-Iranian Gostan and Gostana, the names of the town and region around it, respectively.
