Bian renamed his realm to Great Tang (大唐). Taking on the name of Tang increased his status. Such a move could be easily construed to mean "the potential unification of [Chinese] territories under one ruler." Li Jing was defeated in 958 by Later Zhou Emperor Chai Rong. The Southern Tang were forced to cede their territories north of the Yangtze and become a vassal of the Later Zhou. Li Jing additionally had to renounce claims to emperorship. The rump state was centered on Jiangnan, which was used by both the Later Zhou and the Song to refer to the Southern Tang. Later Zhou correspondence called Li Jing the "Ruler of the State of Jiangnan" (江南國主). He however used the title "Ruler of Tang" (唐國主) and "Seal of Tang" (唐國之印) for the government. Li Yu, the third and final Southern Tang monarch, initially used the title and seal of his father. He attempted to demonstrate obeisance to Emperor Taizu after the Song conquest of Southern Han. Li Yu created a more modest "Seal of Jiangnan" (江南國印) and abandoned "Ruler of Tang" in favor of "Ruler of the State of Jiangnan", which remained used until 976 when he surrendered to the invading Song armies. Taizu gave Li Yu the humiliating title of Marquis of Disobedience (違名侯) when he arrived in Bian. Historical texts produced during the Song dynasty were named after Jiangnan, with variants of Jiangzuo (江左) and Jiangbiao (江俵) also used. By not using the formal name it claimed, authors denied the Southern Tang "the status of an independent state." Reign titles of rulers were likewise seen as unacceptable and their personal names were used exclusively. Background Yang Xingmi was the Jiedushi of Huainan Circuit during the final years of the Tang dynasty. Throughout a series of conflicts with neighboring officials he expanded his control over most contemporary Jiangsu and Anhui, along with parts of Jiangxi and Hubei. In 902 Emperor Zhaozong recognized Yang Xingmi's conquests and granted him the title of the Prince of Wu (吳王). He ruled for three more years and died in 905. Yang Wo succeeded his father as the Prince of Wu. In 907 the last Tang Emperor was evicted from power by Zhu Quanzhong, who declared the Later Liang dynasty. Yang Wo did not recognize this regime change as legitimate and continued to use the Tang era name of 'Tianyou'. Without a reigning Tang emperor,