Overview
Learchus was an adviser in the government of the Kingdom of Cyrenaica during the reign of king Arcesilaus II. Learchus is best known for perpetrating the murder of this very same Arcesilaus II.
Early life
Little is known about Learchus, besides what is written in Plutarch's Moralia and the Histories by Herodotus, who mentions him in passing. Learchus appears to have been an early acquaintance of murder, having killed a Cyrenaean noble who was the husband of the Princess Critola and father of Queen Eryxo.
Rise to power
When Battus II of Cyrene died, his son Arcesilaus II ascended the throne, along with his queen, Eryxo. Arcesilaus appointed Learchus as his advisor. Herodotus states that Learchus was his brother, but Plutarch contradicts him in saying that Learchus was an ill-mannered and vicious friend. A further contradiction is presented in that Herodotus speaks of the activities of Learchus as the activities of the "brothers of Arcesilaus" and does not mention Learchus by name until he is identified as the regicide of Arcesilaus. Arcesilaus followed the counsels of Learchus and became increasingly tyrannical. It is in this manner that Arcesilaus gained the epithet "the Oppressor." During this time, Learchus was secretly plotting to overthrow Arcesilaus and become Cyrenaica's new king, and he manipulated Arcesilaus into ordering the banishment or death of many Cyrenaean nobles.
Exile
When Arcesilaus found out about Learchus’ plotting, they quarrelled over the kingship and Learchus falsely blamed all misdoing on the king. Arcesilaus then ordered Learchus and his supporters to be exiled from Cyrenaica.
From Wikipedia (CC BY-SA 4.0).