The most beautiful woman in Greece who was best known for being the cause of the Trojan War. She was half divine: her father was Zeusand her mother Leda, who had been seduced by the god in the shape of a swan. Her cousin was Penelope, Odysseus's wife, her brothers the famous twins Castor and Polydeuces(lat. Pollux) and her sisters Clytemnestra and Timandra. Because her stepfather Tyndareus had neglected making sacrifices to Aphrodite, the three sisters had been cursed to all become adulteresses.
According to another version it was Nemesis who was seduced by Zeus in the shape of a swan. The eggs were then taken to Leda to look after. The reason Helen was conceived was that Zeus wanted to kill off a part of humanity since he thought Earth was overpopulated; thus Helen would be his tool.
Helen was beautiful already as a child, and the hero Theseushad kidnapped her at one point, so that she would be his wife one day. Her twin brothers came to her rescue and brought her back to their mother.
When the time came for her to marry, many men courted her, amongst them Odysseus. The latter made all the men promise to respect her decision and to protect whomever she chose. Finally she chose Menelaos, king of Sparta and brother of the mightiest king of Greece: Agamemnon.
Aphrodite promised her to prince Paris of Troy as a bribe when he was forced to decide who was the most beautiful goddess. By then Helen was already married to Menelaus and when the couple were visited by Paris, they treated him with great hospitality. Aphroditemade Helen fall for Paris, and together the lovers eloped to Troy.
On discovering what had happened, Menelaus asked his brother to summon the Greek kings and heroes to go to war against Troy. Menelaos eventually got Helen back, and after a difficult journey, taking them to places like Cyprus and Egypt, they went back to Sparta, had a daughter, Hermione, and lived happily ever after.
According to a later version, Helen had been in Egypt all along and the woman in Troy was only a ghost copy of her.