After its fall in 670, the Tuyühu Empire split into an Eastern and Western Kingdom. The Eastern Kingdom existed on the eastern side of the Qilian Mountains and increasingly migrated eastward into central China, whereas the Western Kingdom existed under the leadership of the former exile Khan, Dayan, in Tibet. As the An Lushan Rebellion shook up the Tang court and caused its emperor to flee, Tibet overtook the entire territory of Tuyühu until internal turmoil developed within the Tibetan government and massive revolts brought an end to its rule. Through this period, the Xianbei underwent massive diasporas over a vast territory that stretched from the northwest into central and eastern parts of China, with the greatest concentrations found by Mt. Yin near Ordos. In 946, the Shatuo Turk, Liu Zhiyuan, conspired to murder the highest Xianbei leader, Bai Chengfu, who was reportedly so wealthy that his horses had silver mangers. With that stolen wealth, which included an abundance of property and thousands of fine horses, Liu established the Later Han (947-950), the shortest dynasty in Chinese history, lasting only four years. The incident took away the central leadership and removed any possibility for the Xianbei to restore the Tuyühu Empire.