Emperor Xu%C4%81nzong of Tang

Emperor Xunzong of Tang was a later emperor 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 Dynasty. Succeeding emperors after Xunzong would either be too young or be dominated by eunuchs or warlords. Emperor Xunzong was the 13th son of Emperor Xianzong and an uncle of the previous three emperors, Emperor Jingzong, Emperor Wenzong, and Emperor Wuzong.

Li Yi was born in 810, at Daming Palace , as the 13th ofknown sons of thenreigning Emperor Xianzong. His mother was Emperor Xianzongs 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 Xianzongs palace to be a servant girl to Emperor Xianzongs 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 Yis older brother Li Heng, born of Consort Guo, became emperor , 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.

Source: Wikipedia