From Homer’s Odyssey we learn about the two brothers Amphion and Zethos, as the founders of Thebes and that it was them, who built the big walls of the city, but according to Apollodoros and others, it was Kadmos.
His sister Europa was carried by Zeus, disguised as a bull, from Egypt to Crete, where she bore her three children Minos, Rhadamanthos and Surpedon.
Kadmos, in search for his sister, arrived at Delphi, where he was told to follow a cow and built a city, in the spot where the animal would lie down. According to the myth, the cow stopped at the later Acropolis, Kadmeia.
There are numerous myths about the accomplishments of Kadmos. He killed the Dragon (an offspring of Ares), who was guarding the fountain Areia. Godess Athena told him to sow the dragon’s teeth into the earth and from them, they sprang armed men (Sparti), who killed each other, surviving only five (Chthonius, Echion, Hyperenor, Pelorus, Udaeus).
From these five, the noble families of Thebes arose, calling themselves Sparti. There are also many myths about the four daughters of Kadmos.
One of them, Agave, married Echion and in his reign the God Dionysos appeared for first time in Greece to establish his rights and obtain divine honor. Kadmos and the famous Theban prophet Teiresias accepted him, but not Pentheus, the son of Agave, who was strongly opposed to his wild ceremonies.
He was avenged by Dionysos, with the help of his mother Agave, who in a state of Bacchic fury, torn him to pieces and brought his head to Thebes.
Kadmos with his wife Armonia retired in Illyria. Kadmos ought to have ruled wisely, in order to secure a place, in the difficult to enter Elysium as the ancient people believed that went after his death.