Of the four known oratories attributable to Antonio Vivaldi, Juditha triumphans is the only surviving work. Already acknowledged as a masterpiece when the composer’s unpublished works were rediscovered in the 1920s, this oratory for five solo voices, chorus and orchestra (including several unusual obbligato instruments – mandolin, chalumeau, clarinets, flutes, organ, viola d’amore, and a concert of viole da gamba, etc.), this work was composed for the choir girls of the Ospedale della Pietà in Venice, where it was performed in 1716. The libretto by Giacomo Cassetti is in Latin (as was customary in the Venetian ospedali), and is the adaptation of the biblical story of Judith as an allegory of Venice’s military struggle against the Ottoman Empire in those years. The characterisation of Holofernes is particularly interesting. Although he is officially the villain in the plot, in the libretto and music he is handled with unexpected sympathy. Music historians often cite Juditha triumphans as an example of the trend towards opera in the 18thcentury oratories, and it stands out for the high standard of the very original music.