Although she has a small role in Homer's epic poem The Iliad, Helen has a profound impact on the action of the plot. She is, after all, the primary cause of the Trojan War, during which the poem is set.
Prior to the events of the poem, Paris is tasked by Zeus to determine which goddess is the most beautiful: Hera, Aphrodite, or Athena. Each goddess offers Paris a reward in an attempt to earn his favor and win the contest. Aphrodite ultimately wins Paris's vote with a promise to make the most beautiful woman in the world his wife. However, Aphrodite neglects to mention that Helen, the most beautiful woman in the world, is already married to King Menelaus of Sparta. This obstacle does not stop Paris from perusing Helen.
There is debate as to whether Paris kidnapped and raped Helen or she fell in love with him and willingly left Menelaus. Either way, Helen leaves Sparta for Troy and sparks the Trojan War, becoming "the face that launched a thousand ships."
It is not long before Helen's love for Paris fades. She feels guilty for the many lives lost on her account and she is homesick. Most of the people of Troy resent her for causing the Trojan War. She misses her home, family, and friends. She deeply regrets her decision to be with Paris. In book 3, she speaks with her father-in-law, King Priam of Troy, about her discontentment:
I respect and reverence you, dear father-in-law, I wish I had chosen death rather than following your son, leaving behind my bridal chamber, my beloved daughter, my dear childhood friends and my kin. But I did not, and I pine away in sorrow.
Helen misses her daughter, Hermione, and the life she had before running off with Paris.
Helen regrets her decision to be with Paris, and her resentment of him intensifies as the war progresses. She is disgusted by Paris's cowardly behavior when he fights Menelaus. Paris initially retreats out of fear when he is challenged by Menelaus. After he is scolded by Hector for his cowardice, Paris agrees to fight the Spartan king. During their battle, Menelaus drags Paris by the strap of his helmet. Aphrodite interferes. She breaks the helmet strap and takes Paris off the battlefield to his room in the palace. There, he is scolded by Helen:
So you have left the field: I wish you had died there, at the hands of that great soldier who was once my husband. You used to boast you were a better man than Menelaus, beloved of Ares, a finer spearman, and with a stronger arm. Go back, then, and challenge him, man to man. But my advice would be to stay here, not fight hand to hand with red-haired Menelaus, nor taunt him rashly, lest his spear conquers you.
Helen emasculates and chastises Paris and thinks he is a lesser man and warrior than her former husband, Menelaus.