Castor and Pollux were twin heroes in Greek mythology. Pollux is also called Polydeuces. Castor and Pollux are often called the Dioscuri, which means the sons of Zeus. Zeus was king of the gods. But it was said that only Pollux was Zeus’s son, and that Castor was the son of Tyndareus, the husband of their mother, Leda. The sisters of Castor and Pollux were Helen of Troy and Clytemnestra, the wife of Agamemnon, who was king of Mycenae (or Argos). The two brothers were good companions and became, as gods, patrons of athletes and protectors of sailors at sea. Castor and Pollux had power over winds and waves.
Castor and Pollux quarreled with their cousins, Idas and Lynceus. Idas killed Castor. Then Pollux and Zeus killed Idas and Lynceus. Pollux, an immortal as the son of Zeus, begged to share his immortality with Castor. As a result, the brothers spent every second day on Mount Olympus—the home of the gods—and the rest of the time in Hades, the land of the dead. According to another version of the story, they were placed together in the sky as the constellation Gemini, or The Twins.
See also Gemini.