In Greek mythology, Marsyas was a Phrygian satyr (or silenus) famed for the aulos. He took up the double pipes Athena had cast away, challenged Apollo to a musical contest, and when he lost was flayed alive near Celaenae; tears for him became the river Marsyas. Literary sources stress hubris and divine justice; Romans also cast him as a symbol of free speech in the Forum.
Adapted from Wikipedia, "Marsyas" · CC BY-SA 4.0
I.Family and the aulos
When a genealogy is given, Marsyas is son of Hyagnis, or of Oeagrus, or of Olympus — the last also named as his pupil or beloved. Melanippides and later tradition hold that Athena invented the aulos, saw her puffed cheeks in a mirror, threw the instrument away, and cursed whoever took it up. Marsyas found the pipes and mastered them; Pausanias saw Myron's sculptural group of Athena striking the silenus for picking them up, set before the Parthenon.
II.Contest with Apollo
Marsyas challenged Apollo; the Muses or Nysean nymphs judged, and the winner might treat the loser as he wished. Versions differ: Hyginus has Apollo win by playing the lyre upside-down, a feat impossible on the flute; Diodorus has Apollo add his voice to the lyre and argue that Marsyas's blowing was comparable. The satyr was flayed in a cave near Celaenae; Apollo nailed the skin to a pine by Lake Aulocrene. Ovid dwells on the tears of fauns, satyrs, and nymphs that formed the river Marsyas; Herodotus says the flayed skin was still shown at Celaenae.
Hyginus also brings King Midas into a related judging scene on Tmolus, where Midas prefers Marsyas and receives ass's ears from Apollo. Apollodorus names Marsyas son of Olympus and briefly records the challenge, hanging, and flaying.
III.Wise satyr and Roman liberty
Diodorus praises Marsyas for intelligence and self-control; Plato's Alcibiades likens Socrates to him. At Rome a statue of Marsyas near the comitium stood for centuries as an indicium libertatis — a mark of free speech associated with the plebs and Liber. The gens Marcia claimed descent from him; under Augustus the figure could read as oppositional. Later art (Titian, Ribera, and many others) made the flaying a set piece of Apollonian versus Dionysian struggle. This atlas node is the Phrygian satyr (marsyas-phrygia), not the river alone or Italian eponymic extensions.