Like Gluck’s Orfeo ed Euridice, ‘Scipio’s Dream’ is an azione teatrale. The circumstances of the work’s composition and performance are not entirely clear. It seems that Mozart wrote it in honour of the Archbishop of Salzburg, Sigismund Schrattenbach, who died before it could be performed. It was then brought out (with a simple change of name in the final recitative) for Hieronymus, Count Colloredo, who was later to cause Mozart so much grief; it may have been performed as part of the celebrations marking Colloredo’s entry into Salzburg in April 1772.

The libretto was an old one by Metastasio, first set in 1735, whose sources were Cicero and Silius Italicus. In a dream, Scipio Africanus the Younger is visited by Fortune and Constancy, who require him to choose between them. He finds himself in the heavens, where he meets his father Emilio and his adoptive father Publio. He would like to remain with them but that is not allowed, as he still has great deeds to accomplish. Publio and Emilio refuse to advise him. In the end, Scipio plumps for Constancy; Fortune threatens him with disaster, but he awakes safely back on Earth. In the closing ‘Licenza’ a singer sycophantically addresses the archbishop: the subject is not Scipio but Hieronymus himself.

Metastasio’s libretto includes several of his trademark metaphor arias. Mozart’s setting – a string of recitatives and arias, with one accompanied recitative near the end – is leisurely, with long orchestral introductions and florid vocal writing. The exception, Publio’s ‘Quercia annosa’, provides telling relief; but, to be fair, the 15-year-old Mozart showed good dramatic sense by abridging the da capo repeats.

The Orchestra of Classical Opera, playing on period instruments about a semitone below today’s pitch, are quite wonderful: a special bouquet to Gavin Edwards and Nick Benz, whose B flat alto horns take them into the stratosphere. The singers, most of them new to me, are just as fine. Stuart Jackson manages the melismas and wide leaps of his two arias with confidence and elegance; his fellow tenors, Krystian Adam and Robert Murray, likewise display an exemplary stylishness. Constancy’s first aria and Fortune’s second are bland and pretty well interchangeable: Soraya Mafi gets more out of Fortune’s vigorous ‘Lieve sono’, while Klara Ek seals Constancy’s triumph with a brilliant account of ‘Bianchieggia in mar lo scoglio’, the kind of heroic aria that da Ponte parodied in Così fan tutte. Mozart wrote two versions of the ‘Licenza’ aria: Chiara Skerath sings them both, beautifully.

Ian Page presides over a charming performance, with well-paced recitatives and appropriate, sometimes extravagant decoration. This is minor Mozart, done supremely well.