Le congrès des rois (The Congress of the Kings) was a 3-act French Revolutionary opera of the genre comédie mêlée d'ariettes with a libretto by De Maillot, a stage name used by Antoine-François Ève early in his career, and music by a collaborative of twelve composers (see below).

Participants include the kings of England, Spain, Sardinia, and Naples, the Austrian emperor, and the English minister Pitt.

Madame Cagliostro engages six women, enemies of tyranny, to employ their charms to arouse the passions of these notables and have fun at their expense.

The French, having planted a liberty tree and made a bonfire of symbols of the Ancien Régime, dance and sing in praise of the awakening of the people and the downfall of tyranny.

Its representation of Cagliostro as a virtuous republican was thought scandalous, and the presentation of "the immortal Marat" in the procession of ghosts was deemed disrespectful.