Li Xiaogong
In fall 621, Emperor Gaozu commissioned Li Xiaogong, with Li Jing as his assistant, to launch a major attack on Xiao Xian's Liang state, with a cousin of Li Xiaogong's, Li Yuan (李瑗) the Prince of Lujiang and the other generals Tian Shikang (田世康) and Zhou Faming (周法明) attacking on other fronts. At that time, the Yangtze River had a high water level and was flowing rapidly. While many officers under him suggested delaying the campaign, Li Xiaogong, perhaps with Li Jing's suggestion, decided that indeed, the rapid water was a good opportunity to launch a surprise attack on Xiao Xian's capital Jiangling (江陵, in modern Jingzhou, Hubei). After defeating the Liang general Wen Shihong (文士弘), he put Jiangling under siege, cutting off Xiao Xian's communications with the armies in the rest of his territory. He, again possibly with Li Jing's suggestion, floated the Liang ships that he captured down the Yangtze, to confuse the approaching Liang relief forces into believing that Jiangling had fallen already. Xiao, not knowing that the relief forces were only a few days away, surrendered to Li Xiaogong. By the suggestion of Xiao's official Cen Wenben, who had persuaded Xiao to surrender, Li Xiaogong strictly prohibited pillaging and retribution against Liang generals. The Liang provinces, upon hearing the news of Jiangling's fall, soon largely submitted to Tang. Li Xiaogong delivered Xiao to Chang'an, where Emperor Gaozu executed him.