He was the eighth son of Emperor Muzong, while his mother was an imperial consort surnamed Yang that outlived his father.
Early in Emperor Wenzong's Kaicheng era (836-840), Emperor Wenzong ordered that monthly stipends be given to both Li Rong and Li Chan (who was then the Prince of Ying),[6] and it was said that Emperor Wenzong often treated both him and Li Chan well and more special than other imperial princes.
[7] In 838, Emperor Wenzong's only son and crown prince Li Yong died[7] — probably murdered by household servants.
He summoned Liu Hongyi and another eunuch, Xue Jileng (薛季稜), and asked them to summon Yang Sifu and Li Jue to the palace, ready to entrust Li Chengmei to them.
However, the eunuch army commanders Qiu Shiliang and Yu Hongzhi (魚弘志), hoping to receive credit for supporting a new emperor, opposed Li Chengmei, arguing that Li Chengmei was too young and too sickly.