Emperor Yizong of Tang, né Li Wen, later changed to Li Cui, was an emperor of the Tang dynasty of China. He reigned from 859 to 873. Emperor Yizong was the eldest son of Emperor Xuanzong. After Emperor Xuanzong's death in 859, Emperor Yizong was placed on the throne by the eunuch Wang Zongshi (王宗實), who killed other eunuchs supporting another son of Emperor Xuanzong, Li Zi the Prince of Kui.

Emperor Xuanzong of Tang was an emperor of China's Tang dynasty, reigning from 25 April 846 until his death. 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 and an uncle of the previous three emperors, Emperor Jingzong, Emperor Wenzong, and Emperor Wuzong.