Castor and Pollux
The twin brothers of Helen — one mortal, one divine — who shared immortality by alternating between Olympus and Hades.
The Legend of Castor and Pollux
Castor and Pollux (Polydeuces in Greek) were twin brothers born to Leda, but with different fathers: Pollux was the son of Zeus, who came to Leda as a swan, while Castor was the son of her mortal husband Tyndareus. This made Pollux immortal and Castor mortal — a difference that became tragically relevant. The twins were inseparable: Castor was the supreme horseman, Pollux the undefeated boxer. They sailed with the Argonauts, rescued Helen from Theseus, and fought in the Calydonian Boar Hunt. But in a cattle raid against their cousins Idas and Lynceus, Castor was killed. Pollux, devastated, begged Zeus to let him die too rather than live without his brother. Zeus offered a compromise: the twins would alternate, spending one day on Olympus and the next in Hades. They became the constellation Gemini, and sailors prayed to them during storms — the phenomenon of St. Elmo's fire was thought to be their presence on the mast.
Fun Fact
St. Elmo's fire — the electrical glow on ships' masts during storms — was believed to be Castor and Pollux protecting sailors.
Words We Inherited
English words and phrases that trace back to this myth. See our full guide to English words from Greek mythology.
Explore Further
Dioscuri
🗡 heroCastor and Pollux, the divine twins
The Dioscuri were twin brothers — Castor (mortal) and Pollux (divine) — inseparable in life, who chose to share immortality by alternating between Olympus and Hades.
Iphicles
🗡 heroMortal twin of Heracles
Iphicles was the mortal twin brother of Heracles — born the same night to the same mother but fathered by a mortal, creating the perfect contrast to divine strength.
Castor
🗡 heroNone recorded
Mortal twin of the Dioscuri, famous horse tamer who shared immortality with Polydeuces
Polydeuces
🗡 heroNone recorded
Immortal twin of the Dioscuri and the greatest boxer in Greek mythology
Alexiares
🗡 heroNone recorded
A son of Heracles and Hebe born on Mount Olympus after Heracles' deification, serving as a divine guardian against war
Aloeus
🗡 heroFarming, Giant-Fathers, Hubris
Thessalian king whose twin stepsons the Aloadae nearly defeated the Olympian gods.
Calais
🗡 heroWind, flight
Winged son of Boreas the North Wind who sailed with the Argonauts and drove off the Harpies
Proetus
🗡 heroNone recorded
A king of Tiryns who quarrelled with his twin brother Acrisius over the throne of Argos, an enmity that began in the womb and persisted throughout their lives
Erytus
🗡 heroCombat, brotherhood
Argonaut who sailed with his brother Actor on the voyage to retrieve the Golden Fleece
Amphitryon
🗡 heroidentity, deception
The husband of Alcmene whom Zeus impersonated to conceive Heracles, creating mythology's most famous case of divine identity theft.
Actor
🗡 heroCombat, brotherhood
Argonaut who sailed with his brother Erytus and joined Jason's quest for the Golden Fleece
Helenos
🗡 heroProphecy, combat
Alternative transliteration of Helenus, Trojan prince and seer who foretold the fall of Troy