The first historical reference to him was in 887, as of which time he was serving under Zhao Deyin, who had then claimed the title of acting military governor of Shannan East Circuit (山南東道, headquartered in modern Xiangyang, Hubei) under allegiance to Qin Zongquan—who was formerly a Tang general but who had rebelled against the rule of Emperor Xizong and claimed the title of emperor himself at Cai Prefecture (蔡州, in modern Zhumadian, Henan).
Late in 887, Zhao attacked Tang's Jingnan Circuit and killed its military governor (jiedushi) Zhang Gui.
[1] In 888, the Tang prefect of Gui Prefecture (歸州, in modern Yichang, Hubei), Guo Yu attacked Jingnan and expelled Wang.
[1] Apparently, some time later, perhaps around 890, Wang submitted to Tang imperial authority and was made the military governor of Wutai Circuit.
Wang was unable to resist their attack, and he abandoned Qian Prefecture and withdrew to Fengdu (豐都, in modern Chongqing).