Heroes of Greek Mythology | Details on Cadmus | Cadmus Basics
Born of mortal parents and so, not a demi-god, Cadmus was sent by his father the king on a quest that made Cadmus one of the city-founding heroes. Cadmus' wife was a daughter of the hero's divine nemesis.
Cadmus probably came from the Phoenician city of Tyre, although he may have come from Egypt. His father was Agenor, son of Poseidon. When Agenor's daughter Europa was abducted by a bull (Zeus in disguise), Agenor sent his sons out to locate her. She gave her name to the area of Europe, although she seems to have settled in Crete, while her brothers settled Phoenicia, Cilicia and Thebes. It was Cadmus who settled Thebes, on the advice of the Delphic oracle.
The family line that Cadmus started with his wife, Harmonia, the divine daughter of Ares and Aphrodite, included Pentheus, Semele, Dionysus, and Oedipus -- all characters from Greek tragedy. In the end, Harmonia and Cadmus were turned into snakes.