Cadmus, a mythical king of Thebes, son of Agenor, king of Phoenicia, and brother of Eu-ropa, who is said to have introduced into Hellas the 16 simple letters of the Greek alphabet. He left his native country in search of his sister Europa, who had been borne off by Jupiter. On making inquiry of the Delphic oracle as to what state he should choose for settlement, he was advised to follow a heifer which would meet him. Cadmus found her in Phocis and followed her into Bosotia, where she sank down on a spot which Cadmus called Cadmea, and which became the citadel of Thebes. He sent some of his company to draw water from a well sacred to Mars. This well was guarded by a dragon, which slew the intruders. Cadmus slew the dragon, and was directed by Minerva to sflw the monster's teeth. He did so, and a host of armed men immediately sprang from the ground, who were called the Sparti, or the Sown. These were about to turn upon Cadmus, but the latter threw a stone amid them, and a fight ensued which did not cease until all were slain except five. These survivors became tractable and helped Cadmus to build a new city.

Cadmus was honored as the founder and patron of Thebes. To recompense him for his perils the gods gave him Harmonia, the daughter of Mars and Venus, for a wife, and honored their nuptials with their presence and with gifts. Cadmus subsequently became king of the Enchelians, fought the Illyrians, and had a son called Illyrius; and finally he and Harmonia were changed into-serpents and removed to Elysium.