Charidemus (or Kharidemos, ‹See Tfd›Greek: Χαρίδημος), of Oreus in Euboea, was an ancient Greek mercenary leader of the 4th century BC. He had a complicated relationship with Athens, sometimes aiding the city in its efforts to secure its interests in the northern Aegean, sometimes working against it. He was castigated by Demosthenes in his oration Against Aristocrates for repeated treacherous actions toward Athens, yet later he received Athenian citizenship and was elected one of its generals. In this capacity he ran afoul of Alexander III (the Great) of Macedon and was ordered into banishment after the destruction of Thebes in 335. He retired to Persia, where he was first honored by the Great King, but was later executed after sneering at the quality of the Persian army.