Kallias, son of Arcidamus (460 BC-) was a Greek slave who lived in Megaris during the Peloponnesian War. In 422 BC, he was taken to Megara as a slave when Athens captured his home city, and his brother was also captured and enslaved by the Athenian military. Following the Spartan reconquest of Megaris, Kallias enlisted the help of the mercenary Kassandra in killing the remaining Athenian soldiers in Megaris to avenge his enslavement, and he paid Kassandra for her success.