u-po was an ancient Chinese ghost with revenge on his mind. Before he died, Tu-Po served as a minister to Chinese Emperor Hsuan (lived 827-783 B.C.). The two had a disagreement, and Hsuan had Tu-Po killed in about 786 B.C., despite warnings that Tu-Po would come back and haunt him.
Tu-Po did a lot more than haunt the emperor: Three years later, in 783 B.C., "Hsuan was killed with an arrow fired by an apparition resembling Tu-Po in front of an assembly of feudal lords," wrote Chinese philosopher Mo Tzu (lived 470-391 B.C.). (Translation by Yi-pao Mei, from "The Complete Book of Ghosts" by Paul Roland.) (Image Credit: Public domain, courtesy Wikimedia)