Greek Mythology Notes

Castor and Pollux (Twins)

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Κάστωρ καὶ Πολυδεύκης
The divine twins who share immortality

The twin brothers of Helen — one mortal, one divine — who shared immortality by alternating between Olympus and Hades.

The Myth

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:

Gemini

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