Emperor Xuanzong of Tang (July 27, 810 – September 7, 859) (reigned April 25, 846 – September 7, 859) was an emperor in the latter part of the Tang dynasty of China. Personally named Li Yi, later renamed Li Chen (), and known before his reign as the Prince of Guang, he was considered the last capable emperor of Tang China. Succeeding emperors after Xuanzong would either be too young or be dominated by eunuchs or warlords. Emperor Xuanzong was the 13th son of Emperor Xianzong (r. 806–820) and an uncle of the previous three emperors, Emperor Jingzong, Emperor Wenzong, and Emperor Wuzong. To distinguish Emperor Xuanzong from his ancestor Emperor Xuánzong (personal name Li Longji), as their temple names are rendered identically in Wade–Giles and when pinyin tonal marks are not used, Xuanzong is occasionally referred to as Xuanzong II in western sources; in Chinese, however, their temple names (宣宗 for him and 玄宗 for Li Longji) are clearly distinct and this device is not used. Background Li Yi was born in 810, at Daming Palace (), as the 13th of 20 known sons of then-reigning Emperor Xianzong. His mother was Emperor Xianzong's concubine Consort Zheng, who had previously been a concubine of the warlord Li Qi and who, after imperial forces defeated Li Qi in 807, was taken into Emperor Xianzong's palace to be a servant girl to Emperor Xianzong's wife Consort Guo, but who at some point bore Li Yi for Emperor Xianzong. Consort Zheng is not known to have borne any other children for Emperor Xianzong. After Emperor Xianzong died in 820, Li Yi's older brother Li Heng, born of Consort Guo, became emperor (as Emperor Muzong), and in 821, when Emperor Muzong created a number of his sons and brothers to be imperial princes, Li Yi was created the Prince of Guang. As imperial prince In Li Yi's youth, he was said to be shy and a poor speaker, and (falsely) considered by others to be unintelligent. Later, during the reigns of Emperor Muzong's sons Emperor Wenzong and Emperor Wuzong, Li Yi was said to try to hide himself from the political scene, and rarely spoke anything at all. When the emperors visited the imperial princes' residences, known as the Sixteen Mansions, they would, as a game, try to get Li Yi to speak, and they referred to him as "Uncle Guang." It was said