Bagoas (Persian, Old (ca.600-400 B.C.);: Bagāvahyā|script=Latn; Greek, Ancient (to 1453);: Βαγώας, Greek, Ancient (to 1453);: Bagōas) was a eunuch in the court of the Persian Empire in the 4th century BC. Bagoas was a courtier of Darius III and later of Alexander the Great. He is mentioned in just three surviving sources, but his existence is now generally accepted, and as distinct from Bagoas the Elder, who attempted to assassinate Darius III.
The fullest surviving account of Bagoas is given in the Latin Historiae Alexandri Magni, "Histories of Alexander the Great"' by Quintus Curtius Rufus, a first century Roman historian, and in a 1468 French translations of the same, Livre des fais d'Alexandre le grant. Rufus focuses on the degeneration of Alexander, and illustrates this with an account of the machinations of his eunuch, Bagoas. Bagoas is described as "in the flower of his youth," and was used first by Darius III and was given to Alexander by Nabarzanes. In this account, Alexander takes Bagoas as a lover and the enuch gains influence with him. The Persian satrap Orxines earns the enmity of Bagoas by refusing to pay him respect in court, claiming it is not Persian custom to pay respect to men used as women, and refers to Bagoas as a whore. Bagoas thus manoeuvres to have Orxines accused of plundering the tomb of Cyrus the Great, and the satrap is executed for this crime. In his final words, Orxines decries the state of affairs by which the enuch is now the king. In so doing he points to the influence Bagoas had gained over Alexander.
According to Plutarch, Bagoas, Alexander's favourite, won a dancing contest after the Macedonian crossing of the Gedrosian Desert. Bagoas came and sat beside Alexander, still in his performer's costume. The Macedonian troops, with whom Bagoas was very popular, applauded and demanded that Alexander should kiss Bagoas, and he did so.