Hipparkhos (or Hipparchus) (d. 514 BCE) was a member of the Athenian ruling class, and a son of the late tyrant Peisistratos. Hipparkhos was assassinated by Harmodios and Aristogeiton after a series of tit-for-tat insults between the former and Hipparkhos. While the two had sought to overthrow the tyranny of Hipparkhos's brother, Hippias, they were ultimately unsuccessful. However, after Hippias was overthrown a few years later, Harmodios and Aristogeiton came to be viewed as martyrs to democracy, and Hipparkhos was placed in the role of "tyrant".
During his journey to Athens, the Persian eunuch Mithredath was shown a base where a statue once stood. On the base was the writing "Harmodios and Aristogeiton, those who slew the tyrant Hipparkhos." When his guide, Polydoros explained what a tyrant was, Mithredath found the idea of a statue in a marketplace to celebrate the killers of a city ruler to be madness.