Dramma serio per musica in two acts.

Libretto written in separate numbers between 1806 and 1809 by Vincenzina Viganò Mombelli.

First performed in the Teatro Valle in Rome on 18 May 1812.


Act 1

At the court of Polibio, King of Parthia, Polibio publicly tells a young man, Siveno, that although Siveno is not his son, he is happy to call him son and to treat him as a son.  Siveno acknowledges this gratefully, saying that he owes his life to Polibio.  They embrace, saying that only death will break the bond between them.  Polibio tells Siveno that to cement their relationship, he wants Siveno to marry his daughter Lisinga.  Siveno, already in love with Lisinga, is overjoyed.  In fact, Siveno had been brought to Parthia as a child by a supporter of Demetrio, King of Syria, to escape a violent insurrection in Syria.  Military music is now heard, and a courtier, Onao, tells Polibio that a messenger from Syria has arrived, followed by a substantial army.  Polibio tells his courtiers to be on their guard and instructs the messenger to be brought in.


The messenger is Demetrio, but he introduces himself as Eumene and announces that he brings peace, greetings and gifts from the Syrian king to the Parthian king.  Polibio is suspicious and asks why.  Eumene tells him that in Polibio’s palace there is a young man, Siveno, the son of a loyal Syrian minister named Minteo who has now died.  He says that Demetrio was very fond of Minteo and now wants Siveno to be returned because he is the only link with Minteo left.  Polibio refuses point blank, saying that he loves Siveno and intends that Siveno should succeed him as king.  Eumene threatens to use force to get Siveno back and Polibio replies that he will meet force with force.  When Eumene/Demetrio tells Polibio that he will have cause to repent of this decision, Polibio asks what right Eumene has to question his judgment and orders him to leave.  After a bitter exchange which inflames both men’s anger, Eumene leaves.


Act 2

In a magnificently adorned temple, Siveno welcome the courtiers and people to his marriage.  Polibio greets him, calling him ‘son’.  A choir sings a wedding hymn and Lisinga calls upon the gods to make everyone as happy as she is.  Polibio calls the lovers to the altar and they make their wedding vows, swearing everlasting love and loyalty.  Polibio is clearly upset by something, and when Siveno and Lisinga question him, he tells them about the meeting with Eumene and the demand from Demetrio for the return of Siveno.  Siveno immediately says that he will be the first to take up arms against the Syrians and Lisinga too swears that she will do her bit.  Polibio is torn by the dilemma he faces and when Lisinga leaves along with the whole court, Polibio tells Siveno how much he fears losing him.  Siveno tries to reassure him by telling him that heaven is just and that he will do all he can to help Polibio.  They leave and Onao tells one of Lisinga’s maids, Olmira, that although Syria might boast about its heroes, the Parthians will give as good as they get.  Olmira has his misgivings about the happiness of Siveno and Lisinga but Onao tells her that if there has to be a battle, the peace which will follow it will make it worth the fight.


Elsewhere in the city, Demetrio and his retinue are planning an attack.  Demetrio has bribed guards and servants to let them into the royal palace, where he plans to seize Siveno, whom he refers to as ‘beloved son’.  He encourages his men to be brave.


In her suite, Lisinga is preparing for bed but is restless; Demetrio and his men sneak into the room and, mistaking her for Siveno, seize her.  Lisinga calls for help and Demetrio, surprised that he has taken the wrong person, decides to keep Lisinga as a hostage.  He and his men set the room on fire and although Polibio and Siveno respond to Lisinga’s cries, they cannot get through the flames.  Lisinga faints and Demetrio takes her away as Polibio and Siveno keep calling to her in their frustration.


Act 2

In Polibio’s quarters, a group of courtiers express their concern for the pressure he is under, while Polibio appeals to them for suggestions about where Lisinga might have been taken – he has looked everywhere and there is no sign of her.  Siveno encourages him to be brave and sets out to lead a search party.  In a secluded spot outside the city, Olmira and Onao discuss the situation and decide that the national crisis and their king’s distress are more important than their own love.


Demetrio and his men are hiding with Lisinga.  He reassures her that he too loves Siveno and that he will not harm her, but Lisinga is not convinced.  Suddenly, Siveno’s and Polibio’s voices are heard – they have found Demetrio’s hiding place (they still think that he is Eumene, an envoy from Demetrio).  Lisinga calls out and Demetrio threatens to kill her if Siveno is not returned to him.  This tense stand-off continues for a while, and Lisinga bizarrely tells Demetrio to kill her rather than cause Polibio more distress.  Suddenly, Demetrio sees a medallion around Siveno’s neck and declares that Siveno is actually his own son.  Immediately, he capitulates and the two fathers exchange children.  Polibio embraces Lisinga gratefully while Demetrio embraces Siveno.  But this fragile peace does not last: Lisinga calls on her husband Siveno to join her but Demetrio will not give up his son.  Polibio offers to let Eumene live in peace in his palace but Demetrio angrily rejects this, separates the lovers and leaves with Siveno.


Alone, Demetrio tells Siveno the whole story: Siveno is not the son of a loyal minister named Minteo, but his own son (although he does not tell him that he is actually Demetrio).  He says that he gave his young son to Minteo to ensure his safety during an attempted coup in Syria.  Siveno acknowledges his father, but pleads to be allowed to return to his wife.


Back in Polibio’s court, Onao reports that he has secretly observed the disposition of Demetrio’s men and has heard Siveno weeping.  Lisinga is still heart-broken and Polibio tells her to have courage because he now knows where Demetrio is.  Lisinga begs to be allowed to bear arms herself and Polibio reluctantly agrees, telling her to encourage all her supporters and to have courage.  Lisinga boldly sings of the vengeance that she will take, while her entourage gloomily predict that she will die in the attempt.


Outside the city, in Demetrio’s camp, Olmira turns up, determined to dissuade Demetrio from causing further grief.  Demetrio, however, is furious that Siveno has now disappeared – he begged to be allowed to go and bring Lisinga back, but appears to have betrayed his father after all.  Demetrio begins to realise that he has himself caused all this anguish and wonders how it will all finish.  His troops try to reassure him that Siveno will return.  Suddenly, Lisinga arrives, waving a sword and declaring that she will kill her abductor.  Siveno, however, appears and kneels in front of her telling her to kill him first.  Demetrio is overwhelmed by this display of filial loyalty and embraces both of the young people before announcing that they must all go to Polibio and tell him of the turn of events.


Led by singing troops, the happy band makes its way to Polibio, who is at first horrified to see Lisinga so cheerful in the company of the man who abducted her and threatened to kill her.  Then Eumene drops his bombshell, announcing that he is in fact Demetrio, king of Syria.  His own troops kneel in surprised homage.  Polibio is open-mouthed and Lisinga is amazed.  Demetrio explains that he wanted to regain his lost son but realised that his task would be even more difficult if his identity were revealed.  He swears eternal friendship with Polibio, urging him to forget all that has happened, and he acknowledges that the future is secure for both nations now that Lisinga and Siveno are united in marriage.  Everybody hugs everybody else and the troops declare that such love will be remembered for ever.




Related OperaStory articles can be found on


  • The life and operas of Gioacchino Rossini

  • The peculiar circumstances of the creation of Demetrio e Polibio, the opera which Rossini did not know he had written

  • The life and family of Vicenza Mombelli, the unconventional librettist of Demetrio e Polibio


  • … and many other fascinating stories about operas and the people who created then in Italy at the beginning of the nineteenth century


© Roger Witts 2007