Yüeh-chih ［月氏］ (PY Yuezhi;  Gesshi): A people who inhabited Central Asia from the third century b.c.e. through the third century c.e. They were nomads of Iranian origin (Tibetan or Turkish according to another account). The Yüeh-chih lived in the region that includes present-day Kansu Province in China and its surrounding areas for several centuries up through the third century b.c.e. In the second century b.c.e., however, the Yüeh-chih were defeated by the Hsiung-nu, who were expanding their base of power in the Mongolian Plateau. The majority of the Yüeh-chih moved westward into Sogdiana (the present-day Samarkand region of Uzbekistan) and then across the river Amu Darya (formerly, the Oxus) into Bactria, an ancient kingdom roughly in the region of present-day Afghanistan. Conquering Bactria, they settled there and established a kingdom, which the Chinese referred to as the Great Yüeh-chih (Ta-yüeh-chih). The Yüeh-chih who remained in the Kansu and surrounding regions were called the Little Yüeh-chih (Hsiao-yüeh-chih). The Yüeh-chih in Bactria then divided the country into five chiefdoms, whose chieftains are thought to have been from among the conquered inhabitants. Around 139 b.c.e., Chang Ch’ien, an imperial emissary of the Former Han dynasty, visited the Great Yüeh-chih kingdom and brought back to China new information about the world to the west. Later, in the mid-first century, the Kushans, whose chieftains had successively ruled one of the five chiefdoms of Bactria, defeated the other four chieftains and assumed power in the region. They established the Kushan dynasty, which displaced the Yüeh-chih kingdom. Nevertheless, the Chinese still called the Kushan kingdom the Great Yüeh-chih, as is evidenced in Chinese Buddhist texts and other literature. The Kushan kingdom extended its power into India and Central Asia. Lokakshema, who brought Buddhism to Later Han China in the mid-second century, belonged to the so-called Great Yüeh-chih. In China, he translated numerous Mahayana Buddhist scriptures. Chih-ch’ien and Dharmaraksha, who produced many Chinese translations of Sanskrit Buddhist scriptures in the third century, were also from the Great Yüeh-chih.