Oeagrus (Ancient Greek: Οἴαγρος, "of the wild sorb-apple") was a Thracian king and the usual mortal father of Orpheus (and often Linus) by the Muse Calliope — though some name Apollo as the true sire. Tradition places his realm in Edonia, Pieria, or by the Hebrus; Nonnus sends him on Dionysus's Indian campaign while Calliope raises the infant Orpheus.
Adapted from Wikipedia, "Oeagrus" · CC BY-SA 4.0
I.Realm and ancestry
Accounts disagree on where Oeagrus ruled. One strand places him over the Edonian kingdom in Mygdonia as son of Charops, whom Dionysus set over the Edones after Lycurgus's death; another links him to Pieria as son of King Pierus and the nymph Methone, fifth generation from Atlas via Alcyone; a third ties him to the Hebrus. He is occasionally called a son of Ares, the god associated with Thrace.
II.Father of Orpheus
By Calliope — or, in variant notes, Clio or Polymnia — he fathers Orpheus and Linus; Apollodorus allows that Calliope bore them "to Oeagrus, or nominally to Apollo." Apollonius opens the Argonaut catalogue with Orpheus born near the Pimpleian height when Calliope wed Thracian Oeagrus. He is also sometimes named father of Marsyas. The Muses as sisters of Orpheus can be styled Oeagrides.
III.Dionysiaca
In Nonnus, Oeagrus leaves Pimpleia on the Bistonian plain to follow Dionysus against the Indians, entrusting newborn Orpheus to Calliope. There he is remembered as singer, harpist, and warrior.