Li Keyong
Biography
Li Keyong was a leader of the Shatuo Turks, a nomadic people who became key military allies of the Tang Dynasty. He was famously known as the 'One-Eyed Dragon' because he lost one of his eyes in battle.
His most famous achievement was leading the 'Black-Clad Army' (Crows) to recapture Chang'an from the rebel Huang Chao in 883. His cavalry was feared for its speed and ferocity, and they were the only forces capable of matching the seasoned rebel veterans.
After the rebellion, Li Keyong became a powerful warlord and a lifelong rival to Zhu Wen. While Zhu Wen eventually usurped the Tang throne, Li Keyong remained a nominal loyalist to the Tang, or at least a defender of the old order against Zhu's 'Later Liang' state.
His descendants would later found the Later Tang Dynasty, one of the Five Dynasties that followed the collapse of Tang. His rivalry with Zhu Wen defined the early years of the fragmentation that would last for over half a century.