First performed in 1830, this was once described as a play on which the "romantic school centered its hopes". The Classicists at the time felt that this play was a threat to everything they deemed important in literature. Set in 16th century Spain, Hernani is a tale of romance and intrigue.

Described in 1912 thusly: "The performance was permitted, so tradition says, in the expectation that the play would discredit the romantic school once and for all. The principal actress, Mlle. Mars, was outraged by Hugo’s imagery, and refused point blank to call Firmin [actor] her ‘lion, superb and generous.’ A goodly claque, drawn from the ateliers and salons, brought the play to an overwhelming triumph, and for fifteen years the dominance of the romantic school was indisputable." ... and "Hernani passes from one cataclysmic experience to another; the whole of life seems to depend on the blowing of a hunting horn.".

This play inspired the opera "Ernani" by Giuseppe Verdi, premiered in 1844.