Giasone (Jason) is an opera in three acts and a prologue with music by Francesco Cavalli and a libretto by Giacinto Andrea Cicognini. It was premiered at the Teatro San Cassiano, Venice on 5 January 1649, during carnival. The plot is loosely based on the story of Jason and the Golden Fleece, but the opera contains many comic elements too.

Giasone was "the single most popular opera of the 17th century". It is rarely revived today, but has been performed by for example English Touring Opera (2013). Recordings include a 1988 version directed by René Jacobs with Michael Chance in the title role. A 2010 production by the Vlaamse Opera, with Christophe Dumaux in the title role, was released on DVD.

Roles RoleVoice typePremiere Cast, 1649Giasone (Jason), leader of the ArgonautsaltoErcole (Hercules), an Argonaut bassBesso, captain of Giasone's guardbassIsifile (Hypsipyle), Queen of LemnossopranoOreste, confidant of Isifile bassAlinda, Isifile's lady-in-waiting sopranoMedea, Queen of ColchissopranoDelfa, Medea's old nursealtoRosmina, a gardener sopranoEgeo (Aegeus), King of Athenstenor Antonio CestiDemo, Egeo's servant, a stuttering hunchbacktenorSole (The Sun, Apollo), protector of MedeasopranoAmore (Love, Cupid), protector of IsifilesopranoGiove (Jupiter)bassEolo (Aeolus)altoZeffiro (Zephyrus)sopranoVolano, spirittenorChorus of Winds, Chorus of spirits, Argonauts, gods, soldiers, and sailors

Synopsis

Prologue Two mythological characters appear in the prologue: Sole (the sun, i.e. Apollo) and Amore (love, i.e. Cupid). Sole opens with an aria about the gloriousness of the day because Giasone (i.e. Jason) will set out leading his Argonauts on a quest to find the Golden Fleece - or so it is expected. Sole is also elated that Giasone will marry his descendant Medea and so he lets forth his brightest light. In the following recitative, Amore chides Sole because no one has asked her for permission for this marriage. She had intended that Giasone marry Queen Isifile of the Island of Lemnos: the two are already married and have had twin children. After Amore's aria, they argue over this problem for the remainder of the prologue without resolution and they intend to fight one another.Jacobs, Rene. Outline generated by following the liner notes and libretto from the compact disc recording of Cavalli's "Giasone" on Harmonia Mundi HMX 2901282.84

Act 1 A recitative begins with the Argonaut Ercole (i.e. Hercules), who complains that Giasone has not awoken yet, even though the sun is shining. He is perturbed because Giasone has grown soft as a result of enjoying the pleasures of love with an unknown woman (actually Queen Medea incognito who has been meeting him this way at night for a year) and as a result he has been neglecting his duties. Captain Besso enters and tries to convince Ercole that all men have their vices and so he should not be too concerned. Ercole, being a man of honor, tells Besso that is too effeminate, to which Besso replies: "Of woman I was born."

Giasone enters and sings the aria "Delizie, contenti" of his contentment in seeking sexual pleasure. Ercole admonishes him for neglecting to prepare for battle and the two discuss duty versus the pleasures of love.

Medea is alone singing a strophic aria "Se dardo pungente" about the pain of desiring love. She is joined by Egeo (i.e. King Aegeus of Athens) and together they discuss their marriage, which Medea would like to terminate. Egeo is unable to deal with this and he asks Medea to kill him with a dagger. She refuses and leaves. Alone, Egeo laments over his lost love with the recitative "Si parte, mi deride?".

Orestes introduces himself as Isifile's (Queen of Lemnos) spy in Colchis on a mission to get information about Giasone, but he is afraid of getting caught. Orestes meets the comic character Demo, who introduces himself to Orestes as a brave and handsome hunchback in the aria "Son gobbo, son Demo". After a lengthy conversation, Demo agrees to meet with Orestes and give him information about Giasone a later time.

Delfa (Medea's nurse) sings the aria "Voli il tempo" about how she has renounced love in her old age. She notices that Giasone is approaching and tells Medea that this is her chance to talk to him.

Giasone addresses Medea, who tells him she knows the identity of his night-time incognito lover and reproaches him for not living up to his duties as father of his twin children. She tells him to wait and she will return with the mother of his children.

Alone, Giasone contemplates his situation (i.e. not knowing which lover has his children) while he waits for Medea to return. Medea returns (with Delfa) and she tells him that she herself is the unknown lover and mother of his children. Giasone is filled with joy upon learning this. Giasone and Medea leave Delfa alone, who wishes the couple well, but questions the virtue of having illegitimate children.

In the countryside with huts near the mouth of the Ibero, Isifile is in a trance and singing the lament aria "Lassa, che far degg'io?" She desperately awaits Orestes return with information about Giasone, who she believes she has lost as a lover.

Later Medea is in her magic chamber performing witchcraft and singing the aria "Dell'antro magico" in order to invoke Pluto (King of the Underworld) and ask him to protect Giasone while he is away seeking the Golden Fleece. A Chorus of Spirits responds to her call and they agree to help Giasone by giving him a magical ring. Ellen Rosand remarks that this is the most famous scene in Giasone. A dance concludes the act.

Act 2 Isifile is waiting for Orestes to return. She is in such grief that she lays down to rest. Alinda (a Lady) then sings a cheerful aria "Per provo so" on the subject of finding new love as a cure for pain.

Orestes arrives and Isifile scorns him for having been absent and tempts him to kiss her, then falls asleep. Orestes sings the love aria "Vaghi labbri scoloriti" and decides to kiss her. She awakens her and tells him she burns for him, but then asks about Giasone. Orestes reports that Giasone no longer loves her, but has another lover in Colchis. Furthermore, he tells her that Giasone is planning to quest for the Golden Fleece and that his ship might have a chance to talk with him when his ship passes by. Isifile sings the aria "Speranze fuggite" interspersed with recitative considering her situation.

At the keep of the fortress with the golden fleece, Medea, Jason and Delfa arrive. Trumpet music and stile concitato gestures suggest the martial atmosphere. The combat between Giasone and the monster ("a proud horned beast") takes place. The strings make drum-like martial gestures in an instrumental sinfonia that accompanies the action.

After the combat, Medea ensures Giasone is not injured. Ercole advises him to leave soon because the people are rising against him for taking the Golden Fleece.

Demo arrives to observe and notes that Giasone is returning to the ships. He sings the comic aria "Con arti e con lusinghe" in which he scorns women for using their wiles and swears that he will never be fooled by their trickery by falling in love. He then reports to Egeo (King of Athens) that Giasone and Medea have fled with the Golden Fleece. Egeo realizes that Medea has left him for Giasone and he is mad with jealousy. He and Demo chase after them.

The scene changes to the Cavern of Aeolus. Here the gods Jove (i.e. Jupiter) and Aeolus resolve to create a storm to shipwreck Giasone so that he will return to Isifile in Lemnos. A Chorus of Winds responds to their commands.

Returning to earth to a demolished harbor and a storm at sea, Orestes and Alinda discuss Isifile's jealousy that has driven her to madness. They sing a duet "Sai, ch'io t'amo" and confirm their love for each other.

Demo and Orestes have a long discussion with Demo complaining about the storm and worries for his life. He reports while Egeo was pursuing Giasone in his tiny skiff he fell into the water and drowned. Moreover, the storm is forcing the Argonauts to land at Lemnos. Orestes will inform Isifile.

Giasone, Medea and the Argonauts (including Besso and Ercole) come ashore at Lemnos. The scene opens with a love duet "Scendi, o bella" by Giasone and Medea. In the recitative that follows, Ercole praises Giasone for having lived up to his manly duties while Medea defends his passionate love for her.

Orestes arrives and tells Giasone that Isifile is looking for him. Gisaone and Medea agree to meet with her, although Medea admits jealousy. She wants to know who Isifile is. Giasone makes up a story that she is a hussy and that he does not love her, but Medea remains skeptical.

Giasone and Medea meet with Isifile. She approaches Giasone, but he reassures Medea that he is not interested in her. Giasone humors Isifile's pleas for him to return. Isifile says that Giasone has given her a child, but Giasone denies that he ever loved her. Isifile's emotion switches from bliss to anger in this mad scene.

Besso again defends Giasone for seeking love in the aria "D'affeto sincero." Alinda answers with the trumpet aria "Quanti soldati" in which she rejoices the arrival of all the soldiers available for maidens of Lemnos as a result of the storm. Besso and Alinda then flirt with each other. When Besso tells Alinda that he is a soldier, she does not believe him because he has no wounds or scars. In the end, they agree to stop fighting and together sing the love duet "Non piu guerra" in trumpet aria/concitato style.

Act 3 Set in a flowery glade, Orestes and Delfa discuss Giasone's conflicting marriages to Medea and Isifile.

In a sleep scene, in which Medea and Giasone sing the duet "Dormi, dormi", they fall asleep in each other's arms after he tells her that he will dream of her beauty.

Besso finds Giasone and Medea sleeping with each other and feels some jealousy, for he too wants to find love. He sings the strophic aria "Non e pui bel piacer."

Isifile then arrives. She has been looking in vain for Giasone and has come to the glade to rest, but then she finds the two lovers sleeping. She awakens Giasone and they argue. Giasone is concerned that Medea will awaken and find him with Isifile. In fact, Medea has awoken but continues to feign sleeping so that she can overhear their conversation. Giasone promises to return the honor he has taken from Isifile. She does not believe him, but Giasone swears and gives her a kiss. Medea now rises and scorns Giasone for his disloyalty. To atone for this transgression, Giasone agrees to have Besso murder Isifile in an aside to Medea, who then leaves, pretending to allow Giasone to return to Isifile. Giasone then instructs Isifile to go in secret to meet Besso in the Valley of the Orseno and ask him if he has carried out his orders.

Giasone meets with Besso and tells him to go to the Valley of Orseno and wait for a messenger who will ask if he has carried out his orders. He instructs Besso to throw the messenger into the sea.

It is night in the countryside, and Egeo (dressed as a sailor) is with Demo (dressed as a peasant with a lantern). Egeo begins with the aria "Perch'io torni a penar" in which he complains about his miserable situation as a slave of unrequited love for Medea. Upon seeing Egeo, Demo, who had believed Egeo was dead, begs for mercy.

Isifile, alone in a moonlit night, is joyful because she believes Giasone has returned to her and she sings the strophic aria "Gioite, gioite." She then starts her journey to the Valley of Orseno.

Orestes asks Isifile to return and feed her hungry twins. She does so, but then hurries on to the Valley of Orseno.

In the Valley of Orseno, Medea sings the strophic aria "L'armi apprestatemi" expressing her rage against her rival with stile concitato gestures. She awaits the forthcoming murder of Isifile, but Besso has not arrived yet.