Princess Ida

Princess Ida; or, Castle Adamant is a comic opera with music by Arthur Sullivan and libretto by W. S. Gilbert. It was their eighth operatic collaboration of fourteen. Princess Ida opened at the Savoy Theatre on January 5, 1884, for a run of 246 performances. The piece concerns a princess who founds a women's university and teaches that women are superior to men and should rule in their stead. The prince to whom she had been married in infancy sneaks into the university, together with two friends, with the aim of collecting his bride. They disguise themselves as women students but are discovered, and all soon face a literal war between the sexes.

The opera satirizes feminism, women's education, and Darwinian evolution, which were controversial topics in conservative Victorian England. Princess Ida is based on a narrative poem by Alfred, Lord Tennyson called The Princess (1847), and Gilbert had written a farcical musical play, based on the poem, in 1870. He lifted much of the dialogue of Princess Ida directly from his 1870 farce. It is the only Gilbert and Sullivan opera in three acts and the only one with dialogue in blank verse.

By Savoy Opera standards, Princess Ida was not considered a success due, in part, to a particularly hot summer in London in 1884, and it was not revived in London until 1919. Nevertheless, the piece is performed regularly today by both professional and amateur companies, although not as frequently as the most popular of the Savoy operas.