As the Agamemnon and Meneleus sailed to each city, many of the kings understandably do not wish to go. Odysseus pretended to be mad. The young Achilles was disguised as a girl. Most, however, were forced to participate. Many had been suitors of Helen, before she was married to Meneleus. Worried that a war would break out over her, Helen's father Tyndareus had made all of the suitors promise to defend Helen for the winner.
All the fleets of the different kings gather together at Aulis, a city situated on the eastern coast of Greece. From there, they plan to sail to Troy. The winds, however, will not blow. This is because the goddess Artemis was angered. There are two different explanations as to why. Either Agamemnon claimed to be a better hunter than Artemis, or cattle sacred to her were killed by the Greeks. The Greeks consult the seer Calchas, who says that Agamemnon's first-born daughter Iphigeneia must be sacrificed.
Agamemnon was torn by this. He obviously did not want to sacrifice his daughter. But if he did nothing and the winds still would not blow, he feared retribution from his army. The Greeks were there against their will, and if they were forced to wait longer or perhaps sent back home after coming this far, they might turn on Agamemnon and Menelaus.
Unable to tell her the truth, Agamemnon tells his daughter Iphigeneia that she is to marry Achilles. She is then brought from Mycenae to Aulis. On the day of the sacrifice, she dresses in the traditional wedding outfit. As she walks up to the temple, she meets her mother Clytemnestra, who is crying inconsolably. Now knowing the truth, Iphigeneia bravely proceeds towards the priests, who will perform the sacrifice. There are two different versions as to what happens next. According to Aeschylus, she is sacrificed. According to Euripides, Artemis at the last moment takes the girl away and leaves a deer in her place.
Whether she was sacrificed or not, the winds began to blow. The Greeks at last were able to continue their voyage to Troy.
Euripides. Iphigeneia e en Aulidi.