This dissertation is an ethnopolitical history examining identity creation and interstate relations across medieval China and Inner Asia. The tenth century has been relegated by traditional Chinese histories as a brief, yet chaotic transitional period centered around the sequential Five Dynasties in North China. Contrary to this dominant narrative, my analysis of excavated materials, paintings, various documents, and diplomatic exchanges —between the Five Dynasties, the Ten Kingdoms, Liao (907-1125), and the Korean kingdoms—reveals a Sino-Inner Asian order with the Inner Asian nomadic group, the Shatuo Turks, at the fore. By fashioning an “elite” identity based on their nomadic roots, the Shatuo Turks legitimated themselves as effective rulers, built multiple states including three of the Five Dynasties and one of the Ten Kingdoms, and ultimately forged a new balance of power across a connected Sino-Inner Asian world. This interstate relations and identity formation of the tenth century marked a watershed in Chinese history by not only establishing precedent for the Covenant of Chanyuan a century later but also fundamentally reshaping the Sino-Inner Asian world for centuries in which Inner Asian nomads could lay claim and rule over China.Diplomatic exchanges indicate a delicate power-sharing arrangement among three main political centers was preferred to a unipolar hierarchy between the hub and its periphery, a power paradigm made solely possible by the Inner Asian nomadic group, the Shatuo Turks. Therefore, I suggest the post-Tang world to be understood as the “New Three Kingdoms,” refuting the established Sinocentric periodization of the “Five Dynasties and Ten Kingdoms” created by the eleventh century literati. Through this portrayal of an interconnected Sino-Inner Asia where inter-state relations and identity were intricately intertwined, I argue that the Shatuo Turks were the architects of a transregional multipolar hegemony of a world where the ethnic, cultural, and political identities of peoples and states were fluid—when China, as a cultural and political hegemon, was gone.