Cotys I or Kotys I was born during the reign of Seuthes I. He became king in 384 BC. On gaining the Odrysian kingdom the Athenians made him their ally. In order to make his position stronger Cotys married his daughter to the Athenian general Iphicrates who soon became the second person in command after the king. With the help of Iphicrates, Cotys managed to unite his territory with those that had been held by Hebryzelmis. As Cotys tried to restore and enlarge his kingdom, including towards the Chersonese, his actions led to increasing tensions with Athens. In the early 370s, the Second Athenian Confederacy was founded with a number of cities and islands joining the Confederacy as a safeguard against the threat from Cotys. In 375 BC probably Cotys supported Hales, leader of Triballi, a powerful Thracian tribe in NW Thrace, in their attack on the city ofAbdera. According to Diodorus, the city was saved only after the intervention of the Athenian general, Chabrias, whose forces then garrisoned the city. In 367 BCAriobarzanes, the Persian satrap of Phrygia, occupied Sestos. Following the revolt by Ariobarzanes against the Persian king Artaxerxes II, in 365 BC, Cotys opposed him and Ariobarzanes' ally, Athens. The Athenians under their general Timotheus were able to gain Sestos and Krithote. Soon after, Cotys went to war with the Athenians for the possession of the Thracian Chersonese. Several Athenian generals in succession fought unsuccessfully against him and his mercenary commander Charidemus. Around this time, a rebellion took place against Cotys, led by Cotys' treasurer Miltokythes. According to Demosthenes, Iphicrates, with the help of Charidemus, bribed the Athenian military and naval commanders to suppress the rebellion. In 361 BC, Charidemus returned to Athens with a treaty from Cotys, proclaiming him an ally. Cotys had successfully retained his kingdom. By 360 BC, Cotys controlled the whole Chersonese peninsula. At the end of September 360 BC, he was murdered by two of Plato’s students from Aenus, Python and Heraclides. Thought previously to be advisers to the King, they murdered him during a feast in his palace, under the pretext that he had wronged their father. Upon their return to Athens, they were proclaimed honorary citizens and rewarded with gold wreaths.
