The rising power of the Khitans also threatened the newly established Second Göktürk Empire (682–745) and the khagan Ashina Mochuo, who had supported their rebellion, now asked the Tang Dynasty to be allowed to ally himself to Chinese efforts in exchange for: an imperial marriage for his daughter, adoption as the son of Empress Wu (diplomatic adoption), the return of Turks in Chinese territories (Hexi) and the restoration of Turkish overlordship of the Khitans.