Greek Hero


Cadmus, an eastern prince, was the founder and first king of the Greek city of Thebes. Throughout his storied life, Cadmus wandered far and wide, fought monsters, and was finally transformed into a serpent.

By Avi Kapach11 min read • Last updated on Apr. 4th, 2022
  • No. After searching for Europa for many years, Cadmus finally gave up and settled in Greece.

  • No. Though Cadmus did fight and kill a dragon, the Hydra was killed by Heracles.

  • According to most ancient sources, Cadmus came from Phoenicia (modern Lebanon). After his travels, Cadmus settled in Greece and founded the city of Thebes.

Cadmus was born in the eastern Mediterranean. His parents were royalty and claimed to be descended from the sea god Poseidon. As a young man, Cadmus was forced to leave home in search of his sister (or, according to some versions, his niece) Europa, who had disappeared (Zeus had carried her off). 

After Cadmus had scoured the earth and finally exhausted his search, he decided to settle in Greece. On a fertile site in the region of Boeotia, he fought and killed a dragon, sowed a race of men who were born from the earth, and founded a city, which he called Thebes.

Cadmus ruled Thebes for many years and had many children. But he suffered immense personal loss. Most of his children and grandchildren died horrible deaths. Eventually, he and his wife Harmonia left Thebes and were transformed into serpents.


The etymology of the name Cadmus is uncertain. It has been connected to the Semitic root qdm, which means “east” (a fitting name, given that Cadmus was from the east). It has also been linked to the Greek verb kekasmai (“to shine”). However, linguist Robert Beekes rejected these derivations and deemed the name pre-Greek.1


  • English



  • Phonetic




Cadmus’ most famous heroic act was killing the dragon that guarded the sacred Ismenian Spring on the site of Thebes. This scene was sometimes represented in ancient art, though depictions of Cadmus are scarce.

After killing the dragon, Cadmus came into possession of its magical teeth. He used these teeth to sow the race of warriors who would inhabit his new city. Eventually, Cadmus and his wife Harmonia were transformed into serpents or dragons themselves.


The genealogy of Cadmus is hopelessly tangled: ancient sources give different accounts of his parents, siblings, and even his children.2 These sources also disagree on the location of Cadmus’ homeland, which was variously identified as Phoenicia3 Tyre4 Sidon5 or even Thebes in Egypt.6

Cadmus’ father was either Agenor7 or Phoenix;8 his mother was either Telephassa/Telephe (the names are interchangeable),9 Argiope,10 Antiope,11 or Tyro.12 In what appears to have been the most familiar genealogy, Cadmus had three brothers, named Phoenix, Cilix, and Thasus.13 Europa, a beautiful maiden famously carried off by Zeus, was the daughter of either Phoenix or Agenor and thus either the sister or niece of Cadmus.14 Europa became the mother of the kings of Crete.

Whatever the precise details, Cadmus’ family was firmly associated with the east. Cadmus’ brother (or father) Phoenix was thought to have given his name to the Phoenicians, who inhabited the Levantine coast of the Mediterranean in antiquity. As a son (or grandson) of Agenor, Cadmus was of divine stock, since Agenor was a son of the sea god Poseidon. 

Cadmus’ wife Harmonia was also of divine descent. With her, Cadmus was usually said to have had two sons (Polydorus and Illyrius)15 and four daughters (Agave, Autonoe, Ino, and Semele). Cadmus’ daughter Semele was loved by Zeus and became the mother of Dionysus. Cadmus was thus the grandfather of one of the most important Olympian gods.

#Family Tree

  • Parents
    • Agenor/Phoenix
    • Telephassa (or Telephe)/Argiope/Antiope/Tyro
  • Siblings
    • Europa
  • Consorts
    • Harmonia
  • Children
    • Polydorus
    • Illyrius
    • Agave
    • Autonoe
    • Ino
    • Semele


#Origins and Search for Europa

According to the best-known versions, Cadmus was born in Phoenicia on the east coast of the Mediterranean. His father was the king of the Phoenicians, named either Agenor or Phoenix. 

Cadmus had a sister (or a niece, according to other versions) named Europa. One day, Europa was walking along the coast and caught Zeus’ eye. Zeus transformed himself into a beautiful bull and approached her. When Europa got on top of him, he carried her away across the sea to the island of Crete.

Rape of Europa, Titian

The Rape of Europa by Titian (1560–1562).

Isabella Stewart Gardner Museum / Public Domain

After Europa disappeared, her father sent Cadmus to look for her. Cadmus was accompanied by several companions and relatives, including his brother Thasus, but though they traveled extensively, they never found Europa. When he and the search party reached Samothrace, a region north of the Greek peninsula, Cadmus’ brother Thasus decided to settle down and founded the city of Thasos.16 Cadmus, however, kept traveling.


When Cadmus reached Greece, he learned from an oracle that he was to stop searching for Europa. The oracle gave him instructions on where to found a new city:

“When on the plains

a heifer, that has never known the yoke,

shall cross thy path go thou thy way with her,

and follow where she leads; and when she lies,

to rest herself upon the meadow green,

there shalt thou stop, as it will be a sign

for thee to build upon that plain the walls

of a great city: and its name shall be

the City of Boeotia.”17

Cadmus did as he was told. He followed a cow until it stopped to rest near a sacred body of water called the Ismenian Spring. 

Cadmus was overjoyed and wished to sacrifice the cow to Athena. But when he sent some of his companions to draw water from the spring, they were killed by the dragon that was guarding it. After a lengthy struggle, Cadmus managed to defeat the dragon.

As Cadmus mourned the loss of his companions, Athena (or Ares, in some versions) came to him and told him to sow the dragon’s teeth. Cadmus did so, and a race of warriors emerged fully grown from the earth. Following Athena’s instructions, Cadmus threw a boulder at the warriors. This caused them to start killing each other. 

Cadmus Sowing the Dragons Teeth by Maxfield Parrish, 1908

Cadmus Sowing the Dragon's Teeth by Maxfield Parrish (1908).

New York Public Library / Public Domain

In the end, five warriors were left alive: according to ancient sources, their names were Echion, Udaeus, Chthonius, Hyperenor, and Pelorus.18 These five helped Cadmus to found Thebes, and they and their descendants were called the Spartoi (“sown men”).


After founding Thebes, however, Cadmus needed to atone for the killing of the Ismenian dragon, which was sacred to Ares, the god of war. Cadmus therefore served Ares for a period of eight years.

In most sources, Cadmus was given Ares’ daughter Harmonia as a bride in return for his faithful service.19 But according to the first-century BCE historian Diodorus of Sicily, Harmonia was the daughter of Zeus (not Ares), and Cadmus had married her in Samothrace.20

Whatever the case, the wedding of Cadmus and Harmonia was a grand affair. All the gods attended. As a wedding gift, Harmonia received a magical necklace that granted its wearer eternal youth. But the Necklace of Harmonia, not unlike the equally coveted Ring of Andvari of Norse mythology, brought nothing but grief to all who owned it.

#The House of Cadmus

Cadmus was destined to witness the deaths of many of his children and grandchildren. 

One of Cadmus’ daughters, Semele, was a lover of Zeus and became pregnant with the god’s child. But Zeus’ jealous wife Hera plotted against Semele. At Hera’s urging, Semele made Zeus reveal himself to her in his true form: a blazing bolt of lightning. As she was merely a mortal, this caused her to burst into flames. Zeus was able to rescue Semele’s child and sew him into his own thigh until he came to term. This was how the god Dionysus was born.21

Another one of Cadmus’ daughters was Autonoe. Her son, named Actaeon, stumbled upon the virginal goddess Artemis one day while he was hunting. Artemis was humiliated that a mortal saw her in the nude. As punishment, she turned Actaeon into a stag, and he was torn apart by his own hunting dogs.22

Cadmus’ daughter Ino, in many traditions, incurred Hera’s hatred because she nursed the infant Dionysus after her sister Semele was killed. Since Dionysus was the illegitimate child of her husband, Zeus, Hera wanted to destroy him and all who loved him (she tried to do the same to Heracles). Thus, Hera drove Ino and her husband Athamas mad, leading Ino to leap into the sea with her son Melicertes. Zeus took pity on her and turned her into the goddess Leucothea.

Finally, the son of Cadmus’ daughter Agave, Pentheus, refused to worship Dionysus when he became a god. Dionysus proved his divinity in a terrible way: he turned Agave into a maenad and caused her to tear her own son Pentheus apart with her bare hands. 


After suffering these domestic tragedies, it was usually said that Cadmus and Harmonia went to the land of the Encheleans (modern Albania). The Encheleans at the time were being attacked by the neighboring Illyrians and had learned from an oracle that they could only win the war if they made Cadmus their king. 

Sure enough, the Encheleans defeated the Illyrians with Cadmus’ leadership, and Cadmus went on to reign over both kingdoms. He had another son, named Illyrius, who succeeded him in Illyria and went on to found several cities.


In antiquity, most traditions had it that Cadmus was transformed into a serpent or dragon sometime after fighting the Illyrians. This metamorphosis was sometimes understood as penance for killing Ares’ dragon years before. Zeus then sent the transformed Cadmus and Harmonia to the Elysian Fields.23

Harmonia and Cadmus by Crispijn Van de Passe the Younger

In this 17th-century Dutch etching of a scene from Ovid's Metamorphoses, Cadmus and his wife Harmonia hug each other as they are turned into serpents.

Rijksmuseum / Public Domain

According to Euripides’ tragedy Bacchae (ca. 405 BCE), however, Cadmus and Harmonia had been transformed into serpents earlier, while still in Thebes. In this version, Dionysus was responsible for the metamorphosis: this was part of his punishment of the Thebans for failing to worship him after he became a god. In their new serpent form, it was decreed that Cadmus and Harmonia would lead a foreign race in a war against Delphi.24


Cadmus received worship in some parts of ancient Greece. In Sparta, there was a heroum (hero shrine) dedicated to him.25

#Pop Culture

Cadmus rarely appears in modern pop culture. He does not feature in any major films or TV shows with mythological subjects. The myth of Cadmus is, however, at the heart of Roberto Calasso’s 1993 novel The Marriage of Cadmus and Harmony.

In the world of the Percy Jackson series, Cadmus is the namesake of Cadmus Hunter, and the myth of Cadmus is retold in Percy Jackson’s Heroes.

The “Cadmus Group” is the name of a strategic and technical consulting firm based in Massachusetts. 

#Further Reading

#Primary Sources


  • Homer: The earliest mention of Cadmus was in the epic poems the Iliad and Odyssey, usually thought to have been composed in the eighth century BCE. In the Odyssey, the goddess Leucothea saved Odysseus from drowning after identifying herself as Cadmus’ daughter Ino (5.333). In the Iliad, the Thebans are often referred to as “Cadmeans” or “descendants of Cadmus” (e.g., 4.385).

  • Hesiod: Cadmus’ marriage to Harmonia and his children by her are described briefly in Hesiod’s Theogony, a seventh-century BCE epic poem (lines 937 and 975–78).

  • Theognis: The wedding of Cadmus and Harmonia is described in the first book of poems attributed to Theognis (15–18), who lived in the sixth century BCE.

  • Pindar: The troubles of Cadmus’ daughters (especially Semele) are treated in Olympian Ode 2 (476 BCE). The marriage of Cadmus and Harmonia is described in Pythian Ode 3 (ca. 474 BCE), as is the ultimate metamorphosis of the couple into serpents. This poem also names Cadmus as an example of a hero whose good fortunes were tainted by suffering.

  • Bacchylides: Cadmus’ genealogy is briefly mentioned in Ode 19 of the poet Bacchylides (ca. 516–451 BCE).

  • Herodotus: The Histories, published around 450 BCE, routinely refers to Cadmus and his relatives as important founding figures in the history of Greece.

  • Euripides: Cadmus is one of the main characters of Euripides’ tragedy Bacchae (ca. 405 BCE), in which he and his family are ultimately destroyed by Dionysus. The myth of Cadmus and the founding of Thebes are also described in Euripides’ Phoenician Women (ca. 408 BCE).

  • Apollonius of Rhodes: The myths of Cadmus and his descendants, and the transformation of Cadmus and Harmonia into serpents, are narrated in the third-century BCE epic Argonautica (e.g., 4.516ff).

  • Moschus: The second-century BCE poet Moschus wrote an epyllion (a mini-epic), usually called Europa, on the myth of Zeus’ abduction of Cadmus’ relative Europa.

  • Strabo, Geography: A late first-century BCE geographical treatise and an important source for many local Greek myths, institutions, and religious practices from antiquity.

  • Pausanias, Description of Greece: A second-century CE travelogue; like Strabo’s Geography, an important source for local myths and customs.


  • Ovid: The myths of Cadmus were told in the third and fourth books of Ovid’s Metamorphoses (ca. 8 CE).

  • Statius: The Thebaid (late first century CE), an epic describing the war of the Seven against Thebes, often alludes to Cadmus as the founder of Thebes.

Mythological Handbooks (Greek and Roman)

  • Diodorus of Sicily, Library of History: A work of universal history, covering events from the creation of the cosmos to Diodorus’ own time (mid-first century BCE). The myths of Cadmus are described in Book 5.

  • Apollodorus, Library: A mythological handbook from the first century BCE or the first few centuries CE. The myths of Cadmus are treated in Book 2.

  • Hyginus, Fabulae: A Latin mythological handbook (first or second century CE) that includes sections on the myths of Cadmus.

#Secondary Sources

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