In one of Verdi’s most frustrating experiences, this opera commissioned by Naples in 1857, was actually premiered in Rome in 1859.  The original score underwent significant transformations as a result of censorship regulations in both Naples and Rome and the disturbing political situation in France in 1858.  The plot concerns the assassination in 1792 of King Gustav III of Sweden, who was killed as the result of a political conspiracy against him.  He was shot while attending a masked ball.