Synopsis of Mozart's Opera, Idomeneo

Performance of Idomeneo
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Set in Greece after the Trojan War, the opera "Idomeneo" premiered on January 29, 1781, at the Cuvilliés Theatre that was once located in the Munich Palace in Munich, Germany. This is considered to be one of Wolfgang Amadeus Mozart's first great operas, written when he was just 24 years old. Although Mozart wrote the music, Giambattista Varesco wrote the words in ​Italian.

Act I

After the Trojan King Priam's defeat, his daughter Ilia was captured and taken back to Crete. While being held captive, Ilia fell in love with King Idomeneo's son, Prince Idamante, but she hesitates to bring her secret into the light. In an attempt to gain her love, Prince Idamante orders the freeing of the Trojan prisoners. Sadly, Ilia coldly rejects his goodwill. He argues that it is not his fault their fathers were at war with one another. When Elettra, Princess of Argos, finds out what has happened, she protests this new idea of peace between Crete and Troy. Though really, her anger stems from jealousy of Ilia. Suddenly, the king's confidant, Arbace, bursts into the room with news that King Idomeneo has been lost at sea. Instantly, Elettra is worried that Ilia, a Trojan, will soon be Queen of Crete due to Idamante's love of her.

Meanwhile, King Idomeneo's life has been spared thanks to the intervening of the god, Neptune. Having been washed to shore on a beach on Crete, King Idomeneo recalls the deal he made with Neptune. Should his life be saved, Idomeneo must kill the first living creature he meets and offer it as a sacrifice to Neptune. Just then, Idamante stumbles across the man. Idamante hasn't seen his father since he was a small child, so neither of them is quick to recognize each other. When Idomeneo finally makes the connection, he tells Idamante to leave without ever seeing him again. Upset at what appears to be his father's rejection, Idamante runs away. The men aboard Idomeneo's ship are happy to be alive. As their wives meet them on the beach, they praise Neptune.

Act II

King Idomeneo returns to his palace and speaks with Arbace for advice. After describing his circumstances, Arbace tells him that it would be possible to substitute Idamante's sacrifice for another should Idamante be sent into exile. Idomeneo thinks it over and orders his son to escort Elettra back to her home in Greece. Later, Ilia meets with King Idomeneo and is moved by his kindness. She tells him that since she has lost everything in her homeland, she will make a new life for herself with King Idomeneo as her father and Crete will be her new home. When King Idomeneo thinks of his past decisions, he realizes that Ilia will never be happy, especially now that he has sent Prince Idamante away in exile. He is tormented by his foolish deal with Neptune. Meanwhile, on the ship nearly ready to depart for Argos, Elettra confesses her love for Idamante and her hope of starting a new life with him.

Before their ship departs at the port of Sidon, Idomeneo arrives to say goodbye to his son. He tells him he must learn how to rule while away in exile. As the ship's crew begins to prepare for departure, the sky turns black and a frightening storm unleashes its great power. Amongst the waves, a large serpent approaches the king. Idomeneo knows the serpent as Neptune's messenger and offers his own life to the god, admitting his fault for breaking their deal.


Ilia strolls through the palatial gardens, and thinking of Idamante, whispers to the gentle breeze to carry her thoughts of love to him. Just then, Idamante arrives with news that a great serpent of the sea is destroying the villages along the coast. After telling her he must fight it, he says he'd rather die than to experience the suffering of having his love never reciprocated. Without hesitation, Ilia finally confesses that she has loved him for quite some time. Before the young lovers can comprehend this special moment, they are interrupted by King Idomeneo and Princess Elettra. Idamante asks his father why he must be sent away, but King Idomeneo does not reveal his true reasons. The king, again, sternly sends his son away. Ilia seeks consolation from Elettra, but Elettra's heart is brewing with jealousy and revenge. Arbace enters the garden and tells King Idomeneo that the High Priest of Neptune and his followers demand to speak with him. When confronted by the High Priest, King Idomeneo must confess the name of the person who must be sacrificed. The High Priest reminds King Idomeneo that the serpent will continue to devour the land until the sacrifice has been made. Reluctantly, he tells the Priest and the followers that the sacrifice is his own son, Idamante. When Idamante's name leaves the mouth of the king, everyone is shocked.

The King, High Priest, and more of Neptune's priests gather at the temple to pray for Neptune's appeasing. As they pray, Arbace, the faithful deliverer of news, arrives to announce Idamante's victory for defeating the serpent. Now plagued with worry, King Idomeneo wonders how Neptune will react. Moments later, Idamante arrives dressed in sacrificial gowns and explains to his father that he now understands. Ready to die, he tells his father goodbye. Just as Idomeneo is about to take the life of his son, Ilia rushes in shouting that she will offer her own life in place of Idamante's. Coming from no specific source, Neptune's voice is heard. He is pleased with Idamante's and Ilia's devotion. He orders that the young lovers be appointed the new rulers of Crete. With such a wonderful turn of events, the people let out a sigh of relief, except for Elettra, who now wishes for her own death. King Idomeneo ushers Idamante and Ilia to the throne and presents them as husband and wife. They call upon the god of love to bless their union and bring peace to the land.