The Han dynasty in Inner Asia was the expansion of the Han dynasty's realm and influence in Inner Asia with a series of Chinese military campaigns and expeditions since the reign of the Emperor Wu of Han. Wars were mainly fought against the nomadic Xiongnu confederation based in the Mongolian Plateau, but also against other states in the Western Regions (especially in the Tarim Basin) like the Saka-ruled (Scythian) Greco-Bactrian Kingdom known to the Chinese as Dayuan. As a result, the Han dynasty at its height greatly expanded its power into Central Asia, controlling most of present-day Xinjiang and portions of modern Inner Mongolia with the establishment of the Protectorate of the Western Regions and the vassalization of Southern Xiongnu.[1][2]