Great great great grandfather to great great great grandson is how Cadmus and Oedipus are related in the play "Oedipus Rex." Specifically, Cadmus is the founder and first ki…ng of Thebes. The royal line is supposed to descend from him. Succeeding generations indeed include the descendants of Cadmus and his wife, first Theban Queen Harmonia: 1. Their son Polydorus, who marries Nycteis; 2. Their grandson Labdacus, whose wife is unspecified; 3. Their great grandson Laius, whose wife is Theban Queen Jocasta; 4. Their great great grandson Oedipus, who unknowingly marries his own mother. (MORE)

The founder and first king of Thebes is the Cadmus that Theban King Oedipus identifies as the line from whom generations of Thebans are living. Cadmus is the princely son o…f King Agenor and Queen Telephassa in Tyre, Phoenicia. On his father's side, Cadmus is the grandson of Poseidon the sea god and Libya. He's the great grandson of Cronus and Rhea. He's the great great grandson of the world's first couple, son Saturn and mother Gaia. On his mother's side, Cadmus is the grandson of the siblings Inarchus and Nilus. He's the great grandson of Oceanus and Tethys. His great grandparents on his mother's side are the siblings of his great grandparents on his father's side. So he's the great great grandson of the world's first couple, by way of both parents. Additionally, Cadmus is the husband of Queen Harmonia. Their marriage is considered the world's first wedding celebration. The couple are the parents of subsequent Theban King Polydorus, from whom Oedipus is the direct descendant. They also are the parents of Princess Agave, from whom the siblings Theban King Creon and Theban Queen Jocasta are the direct descendants. Finally, Cadmus is the direct ancestor of the royal rulers of Sparta. It's through the line of descent from Polydorus to Oedipus that this happens. Specifically, it's Oedipus' son Polyneices whose great great great grandchildren Eurysthenes and Procles are the ancestors of different royal dynasties within Sparta. (MORE)