In Greek mythology, Labdacus was king of Thebes, only son of Polydorus and Nycteïs, and grandson of Cadmus. After a short reign he died young — slain in a border war with Pandion of Athens, or, like Pentheus, torn apart for slighting Dionysus — leaving his infant son Laius under the regency of Lycus. His descendants, the Labdacids, include Laius, Oedipus, and Oedipus' children.
Adapted from Wikipedia, "Labdacus" · CC BY-SA 4.0
I.Family
Labdacus is son of Polydorus (himself son of Cadmus and Harmonia) and Nycteïs, daughter of Nycteus. Polydorus died while Labdacus was a child; Nycteus served as regent, then Lycus. When Labdacus came of age he ruled briefly and fathered Laius.
Through Laius the cursed Labdacid stem runs to Oedipus, Polynices, Eteocles, Antigone, and Ismene.
II.Reign and death
Pausanias places his death in a war with the Athenian king Pandion over borders, while Labdacus was still young. Apollodorus instead aligns him with his cousin Pentheus: he opposed Dionysus' rites and was ripped apart by women in a bacchic frenzy.
Either way the throne again fell to Lycus as regent — this time for the infant Laius — until the later Amphion–Zethus and Laius restorations of Theban kingship.
III.The Labdacids
Though Labdacus himself is a short hinge in the Cadmean succession, his name labels the dynasty whose disasters — the Sphinx, the parricide, the Seven against Thebes, Antigone — dominate Attic tragedy.
This entry is the Theban king only.