- The protagonist of the novel, Theseus is the son of Aigeus, King of Athens, although he believes that he is also the son of Poseidon, the sea-god. Theseus is strong, brave, and passionate, and his courage and daring make him a natural leader who inspires loyalty in all around him.
in-depth analysis of Theseus.
- Asterion, also called the Minotauros, is the power-hungry heir to Minos's throne, although he is not the King's son. Asterion treats other people as objects, and he insults Theseus continually because he refuses to acknowledge his humanity.
in-depth analysis of Asterion.
- King of Athens and Theseus's father. He is a good king but is tired from fighting wars and he does not rule as well as Theseus believes he could rule. He could free his house from the curse of the Mother, but he is unwilling to kill his own son to do so.
in-depth analysis of Aigeus.
- Minos's daughter, Ariadne is the Goddess-on-Earth, the highest Cretan priestess. She does not believe in the gods. She falls in love with Theseus and they escape Crete together, but when she takes part in the sacrifice of the King on Naxos, Theseus leaves her.
- The name for the king of Crete. When Theseus arrives as a bull-dancer, the present Minos is sick with leprosy. Minos no longer believes in the gods, but he aids Theseus because he wants to stop Asterion, whom he hates, and save his daughter Ariadne, whom he loves.
- Theseus's most trusted friend among the Cranes. Amyntor was also one of the Companions in Eleusis. He is a catcher in the bull-dance, and his steadiness and courage help Theseus in their time in Crete.
- The Queen of Eleusis marries Theseus when he kills Kerkyon, the former King. But she is also the chief priestess of Mother Dia, and when Theseus begins acting against custom, she tries to have him killed. She is a passionate woman who considers her life less important than her service to the Mother.
- The Queen's brother, Xanthos is the War Leader in Eleusis. He is greedy and unkind, and he tries to have Theseus killed. Xanthos is killed by Theseus in armed combat, and his own people aid Theseus in that battle.
- Theseus' grandfather is King Pittheus of Troizen. He is a good king who tells Theseus about Moira and that the king must accept his fate as ruler of the people. Pittheus is a good judge of character and believes Theseus will make a good ruler.
- The son of the King of Megara, Pylas is a good warrior and becomes a good friend of Theseus, although he dies at a young age. Pylas senses that Theseus will change the customs in Eleusis, and together they sweep clean the Isthmus Road.
- The hereditary name given to the King of Eleusis, Theseus wrestles and kills Kerkyon in order to assume the title himself. Before Theseus Kerkyon would die each year, but Theseus changes some of the customs in the land once he is King.
- A priestess of the Mother, the Lady Medea is living with Aigeus when Theseus gets to Athens. She wants the King to poison Theseus in order to lift the curse of the Mother that has been laid on his house. When Aigeus sees that Theseus is his son and refuses, she curses Theseus.
- A childhood friend of Theseus', Dexios is his charioteer on the ride through the Isthmus. He is a good friend and a good driver, and when he is killed, Theseus avenges his death.
- Minos' young daughter, Phaedra falls in love with Theseus when she is a young girl, and he promises her that they will get married when she is older. According to legend, he does so, and she causes the troubles that lead to the death of his son.
- The Captain on the Cretan ship that Theseus and the others take from Athens, Lukos is a scheming, intelligent man who wishes to improve his favor at court. He tells Theseus about what he will have to face, but shuns him after he insults Asterion.
- The great bull-dancer in the Bull Court when the Cranes arrive, the Corinthian is brave, proud, and fearless. He dies shortly afterward, but he is always a model to Theseus.
- The major deity in Eleusis, Crete, and all of the Minyan areas, Mother Dia represents the old religion. Some of the priests and priestesses who worship the Mother, like the Queen of Eleusis, are very resistant to change, and do not wish to allow the worship of any other gods.
- The major god throughout the book. Theseus believes that he is Poseidon's son. The rage of Poseidon causes earthquakes and much other damage, and all seafaring peoples pay tribute to him.