Ancient Greek texts name Leda as the daughter of King Thestius of Aetolia. Pausanias wrote in Description of Greece that her father was a son of Ares. Apollodorus listed her mother as Leucippe or Deidameia. Alcman claimed Glaucus and Laophonte were her parents instead. Eumelus argued for Sisyphus and Panteiduia as her true lineage. These conflicting accounts span centuries of oral tradition before being written down. Some sources list up to six siblings including Althaea and Iphiclus. Hyginus named only two siblings while others mention four brothers. The confusion stems from different regional versions of the myth circulating across ancient Greece.
The Swan Disguise
Zeus disguised himself as an injured swan fleeing from an eagle near the river Eurotas. He fell into Leda's lap claiming he needed protection from the predator. Euripides described this moment as Zeus assaulting her under the guise of injury. Ovid noted that Zeus devised this plot specifically to avoid Hera's jealousy. Later that same day, Leda lay with her husband Tyndareus as well. This dual union created a complex family tree where children had different fathers. The story suggests divine intervention altered human reproduction through deception. No calendar date marks when these events supposedly occurred within the narrative itself.Eggs And Fathers
Athenaeus recorded that Leda laid two eggs containing four distinct children. One egg held Helen and Pollux while the other contained Clytemtra and Castor. Pollux emerged as immortal because Zeus fathered him directly. Castor remained mortal since Tyndareus was his biological parent. Some accounts skip the egg detail entirely and describe direct birth instead. Another version states Nemesis gave birth to Helen in an egg found by a shepherd. That shepherd delivered the egg to Leda who kept it in a chest until hatching. Zeus later created the constellation Cygnus to commemorate Helen's birth. These variations show how ancient storytellers adapted core myths for different audiences.