Background Political Beginning in 742, Eurasia entered a 13-year period of major political turmoil, with the regional empires generally suffering "a major rebellion, revolution, or dynastic change." In this year the Second Turkic Khaganate of the eastern Eurasian Steppe was overthrown and then replaced by Sogdian-influenced Uighur rulers. This was apparently the first of several revolutionary events either led by or intimately connected with the merchants and tradespeople involved with the international commerce often referred to as the Silk Road. In 747, the Abbasids began their rebellion against the Umayyad Caliphate in Merv, Khurasan, resulting in the proclamation of a new Abbasid Caliph in about 750. This rebellion also seems to have been organized by merchants and persons identifying themselves as merchants. The western expansion of the Tang Empire was checked in 751 by the defeat of a large expeditionary force led by General Gao Xianzhi in the Battle of Talas in the modern Fergana Valley, with the Abbasid victory attributable to the defection of the Karluk Turks in the midst of the battle. However, the Arabs did not proceed any further after the battle, and the Tang retained their Central Asian territories until the An Lushan rebellion. Further, southern expansion of the Tang was limited by the ineffective, and even disastrous, campaigns against the Kingdom of Nanzhao. However, the concurrent Tang campaign against the Tibetan Empire was proceeding more successfully, with the campaign to capture the Tibetans' Central Asian territories appearing nearly successful. With the assassination of the Tibetan emperor Me Agtsom in 755 in the midst of a major rebellion within the Tibetan polity, final Tang victory over the Tibetan Empire seemed all but assured. However, back in the increasingly financially challenged Chinese heartland, the Sogdian-Turkic General An Lushan had worked himself into a position of trust with the Tang emperor Xuanzong and his consort Yang Guifei. General An Lushan An Lushan was a general of uncertain birth origins, but thought to have been adopted by a Sogdian father and Göktürk mother of the Ashina tribe. Eventually he managed to become a favorite of the reigning emperor of China. His success in this regard is shown, for example, by the luxurious house Emperor Xuanzong built for him in 751, in the capital Chang'an. The house was furnished with luxuries such as gold and silver objects and a pair of ten-foot-long by six-foot-wide couches appliqued with rare and expensive