Empress Irene rules over Byzantium on behalf of her son Isaccio who is not yet of age. This weighs heavily on her because she is secretly in love with the much younger Niceforo, the son of her closest adviser Oreste. Through Niceforo’s sister Eudossa she learns that he is also in love with her. Filled with happiness she plans to take him as her husband. In turn Isaccio is in love with Eudossa and wants to marry  her even against her will, therefore he now wants to become sole ruler. Together with Oreste he incites an uprising. After Irene has announced her engagement with Niceforo, Oreste reveals that years ago he swapped his own son with the son of the Emperor and Empress: Niceforo is therefore Irene’s son, and Isaccio is his. After a  brief moment of shock Irene relinquishes her position and changes from a lovestruck  woman to a loving mother. This opera premiered on 6 February 1738 at the  Hoftheater in Dresden to mark the birthday of Anna, Empress of Russia, who,  however, was not in attendance; whether the work was intended to honour her or as satire can no longer be ascertained. Composer Johann Adolph Hasse wrote the title role for his wife, the star soprano Faustina Bordoni, creating, in the empress plagued  by inappropriate passions and doubts, a role full of scintillating facets that would  demonstrate her art.