Who was Helen of Troy and why was she kidnapped?

Helen of Troy is a greek legend with the suppossed most beautiful woman of greece and the indirect cause of the Trojan war. Shes the daughter of Zeus, either by Leida or by Nemsesis and sister of the Dosurci. Helen ran to Troywith paris who was the son of the Trojan king Priam. when Paris was slain, she married his brother Deiphobus, whom she betrayed to Menelaus when Troy was subsequently captured. Menelaus and she then returned to sparta, where they lived happily until their deaths