About the work
Dramma per musica in three acts by Florian Leopold Gassmann, setting Pietro Metastasio's libretto; it premiered on 29 April 1761 at the Teatro San Samuele in Venice, followed the same year by performances in Lugo and, at carnival 1762, in Vicenza. As with Merope, only the printed libretto of this setting survives; the score is lost.
Plot
The Roman senator Cato defends the besieged city of Utica against Caesar's bid for sole power, while his daughter Marzia is secretly in love with Caesar. Failed peace talks lead to open war; when Marzia's relationship with Caesar comes to light, Cato disowns her. After Caesar's victory, Cato takes his own life rather than submit to one-man rule – an unusually uncompromising ending for an opera seria of its time, which Metastasio later had to soften.
Cultural significance
Metastasio's politically charged subject of republican liberty versus tyranny was set some 30 times and stands out among opera seria librettos for its tragic rather than reconciliatory ending. Gassmann's version came at the end of his first run of Venetian carnival operas, shortly before he moved to the Viennese court in 1763.