A room in the house of the governor
Riccardo is accomplishing his duties as Governor of Boston. Oscar, his page, asks him to approve the list of guests invited to a ball: among them is Amelia, with whom the Count is in love. Renato, Amelia's husband and the Count's faithful secretary, warns him that a plot is being prepared against him, but Riccardo will not listen to the names of the conspirators, preferring to rely on the love of his people. At the same time, yielding to the pleas of his page Oscar, he refuses to sign a decree exiling the fortune-teller Ulrica. He proposes instead to visit Ulrica and invites everyone to meet in her house, where he will be present disguised as a fisherman.
The fortune-teller's house
The Count (as a fisherman) and his friends arrive at the fortune-teller's house. A short while after, a maid arrives announcing that a lady is waiting outside and wishes to speak to the fortune-teller. The latter sends everyone out of the room and goes to fetch the lady from outside. Amelia enters and reveals that she is in love with Riccardo. She asks Ulrica in which way she may free herself of her guilty passion. Riccardo, who recognized Amelia's maid, is concealed in a corner, so he can hear the conversation and is delighted by her confession of love. The fortune-teller tells Amelia that she must gather a magic herb, at midnight, in a sinister place outside the town. Riccardo decides that he will follow her. Amelia leaves the cave and the others all come back in. Riccardo can finally ask Ulrica to foretell his future. Her terrible answer is that he will be killed very soon by the first person who will shake his hand. At this moment Renato enters and shakes Riccardo's hand. Riccardo lets himself be known and at the same time congratulates the fortune teller, joking with her about how absurd her prophecies are.
A lonely place on the outskirts of Boston
Terrified by the ghostly surroundings in this place of ill omen, Amelia arrives on the scene. Her anxiety is increased by the fact that she is torn between her love and her conscience. The arrival of the Count upsets her even more. He pleads with her passionately and succeeds in inducing her to admit her love for him. Renato, her husband, appears suddenly to warn Riccardo that the conspirators are on their way to kill him and exhorts him to take flight immediately. Amelia barely has time to cover her face with a veil to avoid being recognized. After much insistence, Riccardo agrees and then instructs Renato to escort the veiled lady back to the town, making him promise that he will make no attempt to discover her identity. Immediately afterwards, the conspirators Samuel and Tom arrive. They have mistaken Renato for the Count and are confident that the opportunity has arrived to put their plan into effect. On discovering their mistake, the baffled murderers demand to know the identity of the veiled lady. Amelia is forced to unveil. Renato is horrified at discovering the deception of which he has been the victim and is mocked by Tom and Samuel.
Renato has decided to seek vengeance and to join forces with Tom and Samuel, whom he has called to a meeting in his house. He tells Amelia he has decided to kill her but allows her to see her son for the last time, but then relents; instead he will take vengeance upon Riccardo, her seducer. When Samuel and Tom arrive, he informs them of his intentions. It is then decided that only one of them will be the killer. Their three names are put into an urn and Amelia is called upon to draw one out. The lot falls on Renato. An invitation to attend a masked ball arrives from the Count, borne by Oscar; it will provide an excellent opportunity to carry out their plan.
The Count's sumptuous study
Riccardo has decided to cast aside his infatuation for Amelia and signs a document ordering the transfer of Renato and Amelia back to England. Oscar arrives with a note given to him by an unknown lady. It warns the Count to beware at the ball but he takes no notice of the threat.
Renato cleverly tricks Oscar into revealing how the Count will be disguised. Riccardo meets Amelia and bids farewell to her. The sad parting is interrupted as he is stabbed by Renato. As he lies dying, Riccardo tells Renato that Amelia is innocent of all wrong and then pardons his assassin.
The troubled story of Un Ballo in maschera
In 1856 Verdi came to an arrangement with the San Carlo Theatre in Naples for the composition of a new opera to be staged in January 1858. At first the choice of the subject had been on the Shakespearian King Lear with a libretto by Antonio Somma, but this project soon began to fade away. Actually Verdi had requested the presence of Maria Piccolomini for the role of Cordelia, but the singer was not available. Then the composer put King Lear to one side and chose a new subject inspired by a libretto which Scribe had written for an opera by Auber (Gustave III ou Le Bal masqué). This opera had premièred in 1833 and at that time it was still performed in numerous theatres. It was not the first adaptation of the above mentioned opera: the libretto had been translated and modified by Salvatore Cammarano for Il Reggente by Mercadante (Turin 1843).
The subject of the libretto written by Scribe dealt with the murder of the Swedish King, Gustavus III, in 1792 during a masked ball. Verdi asked Somma to translate the libretto in 5 acts by Scribe and to adapt it to be made into a three-act opera. Somma was a renowned man of letters, but all in all a quite inexperienced librettist and therefore Verdi played an active and instrumental role in writing up the text. Verdi and Somma took this decision in October 1857, when there were only three months to go before the scheduled première. Anyway Somma worked very quickly and towards the end of the month the first act was already completed. Three weeks later the second act was ready too.
Lack of time was not, however, the only problem. Verdi had to submit the libretto to the Neapolitan board of censors for its approval. He had already been warned by the executive secretary of the San Carlo Theatre that the board of censors might make some changes as the opera dealt with a regicide and that's exactly what happened. Some of the conditions the censors laid down for the staging of the opera included the changing of the main character from king to duke and the shifting of the time and place. Verdi conveyed to Somma the changes to be made to the libretto and the latter proposed to move the story back to the twelfth century and to set it in Stettino in Pomerania, but although the composer agreed with Somma about the place, he found that the age the librettist had chosen was too rough and violent and it didn't actually suit the the elegance of the characters and the subtlety of the story. Then the choice fell on the seventeenth century and a new title: La vendetta in domino.
In spite of all these attempts to soften the potentially dangerous elements, in January 1858 Verdi reached Naples and was in for a bitter surprise: on arrival the censors had refused the permission to stage the opera with or without the changes of time and place. The attempt on Napoleon III's life at the hands of Felice Orsini, which occurred on January 13th the same year, had deeply troubled the Neapolitan monarchy which at that time was more than ever prejudiced against any references to the regicide, even if it was only on the stage. Moreover the censors insisted that the libretto be completely written again. In order to meet these unalterable requests the San Carlo Theatre consulted another librettist, who created a new opera, Adelia degli Adimari, set in Florence during the fourteenth century. The theatre offered Verdi this new composition, but it was met with his refusal: as a result the theatre brought an action against the composer. The latter promptly replied through his lawyers and he succeeded in having his contract with the Neapolitan theatre annulled, but at the same time he committed himself to staging a new opera the following autumn.
Meanwhile Verdi had already offered La vendetta in domino to the Apollo Theatre in Rome and they had accepted it with the proviso that it had to be submitted to the papal censors. The latter gave their consent on condition that the story was not set in Europe. After taking numerous countries into consideration, Caucasus included, Verdi and Somma decided on the United States at the end of the sixteenth century and they changed King Gustavus III into Riccardo, Count of Warwick and Governor of Boston. Moreover they decided to change the title of the opera by using the original subtitle by Scribe, i.e. Le Bal masqué, which became Un Ballo in maschera.
When the last changes suggested by the censors were made, at last it was possible to stage the opera. From its première, which took place on February 17th 1859, Un Ballo in maschera was a great success. It was also on that occasion that the acrostic "Viva Verdi" was invented: it was a hymn to Vittorio Emanuele, King of Italy, interpreted as a challenge to the Austrians and it spread rapidly throughout Italy. Apart from its role in the patriotic atmosphere of that time, Un Ballo in maschera stands out for its emotional strength and Verdi's genius that found here a new and lively expression. The opera met with success immediately and the Roman critics defined it as a a step forward in Verdi's new style.