Cersobleptes

Cersobleptes (Greek: Kερσoβλέπτης), also spelled Kersobleptes, Kersebleptes, and Cersebleptes, was son of Cotys, king of Thrace, on whose death in 358 BC he inherited the kingdom in conjunction with Berisades and Amadocus II, who were probably his brothers. He was very young at the time, and the whole management of his affairs was assumed by the Euboean adventurer, Charidemus, who was connected by marriage with the royal family. The area controlled by Cersobleptes was east of the river Hebrus.

Charidemus took on a prominent role in the ensuing contests and negotiations with Athens for the possession of the Thracian Chersonese, with Cersobleptes appearing throughout as a mere puppet of Charidemus. The peninsula seems to have been finally ceded to the Athenians in 357 BC, though they did not occupy it with their settlers until 353 BC; although Isocrates is less certain about the earlier date. For some time after the cession of the Chersonese, Cersobleptes continued to assiduously court the favour of the Athenians, being perhaps restrained from aggression by the fear of the Athenian fleet based in the Hellespont.

On the death of Berisades, before 352 BC, Cersobleptes conceived, or more correctly Charidemus conceived for him, the idea of excluding the children of the deceased prince from their inheritance, and obtaining possession of all the dominions of Cotys. It was with this objective in mind that Charidemus gained from the Athenian people, through his party among the orators, the decree in his favour. In response to this outcome, Demosthenes delivered a speech (which still exists) through which he unsuccessfully tried to impeach the mover of the decree, . From a passing reference in Demosthenes' oration, it appears that Cersobleptes had been negotiating with king Philip II of Macedonia for a combined attack on the Chersonese. However, these negotiations came to nothing as a consequence of the refusal of Amadocus to allow Philip a passage through his territory. But after the passing of the Athenian decree, Philip became the enemy of Cersobleptes, and in 352 BC made a successful expedition into Thrace, gained a firm ascendancy in the country and took a son of Cersobleptes as a hostage.

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