EAST TURKISTAN refers to the whole of of East Turkistan, encompassing the Tarim Basin, Junggar (Dzungar) Basin, and the Kengsu Basin. This area includes the territories currently under Chinese occupation, known as the so-called Uyghur Autonomous Region, along with the Subei Mongol Autonomous County, Aksai Kazakh Autonomous County, Dunhuang City (formerly Dukhan), and Guazhou County in Gansu Province, as well as the Lenghu Administrative Zone and the western portion of the Mangnai Administrative Zone in Qinghai Province. Historically, the Jiayuguan (Jiayu Pass) was the official boundary between East Turkistan and China from ancient times until the Manchu Qing Empire’s conquest of East Turkistan in 1759. The total territory of East Turkistan spans  1,828,418 square kilometers (705,956 square miles).