Wang Chengzong
In late 817, the imperial general Li Su captured Wu Yuanji, who was soon executed. When the news of Wu's defeat reached Li Shidao and Wang Chengzong, both became fearful. Wang again offered to surrender two of his six prefectures to imperial control and further sent his two sons to Chang'an to serve as hostages, and Emperor Xianzong accepted his submission. Li Gongdu and another officer, Li Yingtan (), thus persuaded Li Shidao to submit three of his 12 prefectures — Yi (沂州, in modern Linyi, Shandong), Mi, and Hai (海州, in modern Lianyungang, Jiangsu) to imperial control and to send his oldest son Li Hongfang () to Chang'an as a hostage. Emperor Xianzong initially agreed, and he sent the official Li Sun () to Pinglu to comfort Li Shidao.