Castor and Pollux/Polydeuces

In Greek mythology, the inseparable twins or sons of Leda; brothers of Helen and Clytemnestra; protectors of sailors. Their brotherly love was symbolized in the constellation Gemini. Many versions of their birth exist; in one tradition, the boys were fathered by Zeus in the form of a swan, and born from an egg.

In another variation, Polydeuces (Roman Pollux) was Zeus's son, while Leda's husband, Tyndareus of Sparta, was Castor's father. Polydeuces, as son of a god, was immortal, while his brother was subject to old age and death. When Castor died fighting his cousins Idas and Lynceus, Zeus allowed Polydeuces to share Castor's mortality and live on alternate days in the underworld and with the gods. He placed their image in the stars to honour their love.

According to Homer, Tyndareus was father of the twins, while Helen was Zeus's daughter. In a later variant, Leda bore two eggs, one containing the boys, the other Helen.

Heroic deeds The brothers rescued Helen when she was carried off by Theseus, and took part in the heroic Calydonian Boar hunt, organized by Meleager to kill a boar sent by the goddess Artemis. While venturing with the Argonauts on the quest for the Golden Fleece, Polydeuces slew King Amycus of Bebrycia, a champion boxer who had previously killed all strangers through his challenges.

Worship It was believed that Poseidon, king of the ocean, had given Castor and Polydeuces power over the winds and waves. Worshipped by sailors, they appeared during storms in the lights now called St Elmo's fire; a blue-ish, flamelike electrical discharge above a ship's mast.

Their worship spread from Sparta to early Rome after they allegedly intervened on behalf of Aulus Postumius and the young Republic at the battle of Lake Regillus in 496 BC, aiding the fight against the forces of Tarquinius Superbus, the last king of Rome, and his Latin allies.

Art The brothers are usually depicted as warriors, riding great white horses, and sometimes wearing egg-shaped helmets decorated with a star.