Grand opera is a genre of 19th-century opera generally in four or five acts, characterized by large-scale casts and orchestras, and (in their original productions) lavish and spectacular design and stage effects, normally with plots based on or around dramatic historic events. The term is particularly applied (sometimes specifically using in its French language equivalent grand opéra, pronounced: [ɡʁɑ̃t‿ɔpeˈʁa]) to certain productions of the Paris Opéra from the late 1820s to around 1850; 'grand opéra' has sometimes been used to denote the Paris Opéra itself.
The term 'grand opera' is also used in a broader application in respect of contemporary or later works of similar monumental proportions from France, Germany, Italy and other countries.
It may also be used colloquially in an imprecise sense to refer to 'serious opera without spoken dialogue'.
Paris at the turn of the 19th century drew in many composers, both French and foreign, and especially those of opera. Several Italians working during this period including Luigi Cherubini demonstrated that the use of recitative was suited for the powerful dramas that were being written. Others, such as Gaspare Spontini, wrote works to glorify Napoleon. These operas were composed on a suitably grand scale for the Emperor. Other factors which led to Parisian supremacy at operatic spectacle was the ability of the large Paris Opéra to stage sizeable works and recruit leading stage-painters, designers and technicians, and the long tradition of French ballet and stagecraft. The first theatre performance ever lit by gas, for example, was Aladin ou La lampe merveilleuse at the Opéra in 1823; and the theatre had on its staff the innovative designers Duponchel, Cicéri and Daguerre.
Several operas by Gaspare Spontini, Luigi Cherubini, and Gioachino Rossini can be regarded as precursors to French grand opera. These include Spontini's La vestale (1807) and Fernand Cortez (1809, revised 1817), Cherubini's Les Abencérages (1813), and Rossini's Le siège de Corinthe (1827) and Moïse et Pharaon (1828). All of these have some of the characteristics of size and spectacle that are normally associated with French grand opera. Another important forerunner was Il crociato in Egitto by Meyerbeer, who eventually became the acknowledged king of the grand opera genre. In Il crociato, which was produced by Rossini in Paris in 1825 after success in Venice, Florence and London, Meyerbeer succeeded in blending Italian singing-style with an orchestral style derived from his German training, introducing a far wider range of musical theatre effects than traditional Italian opera. Moreover, Il crociato with its exotic historical setting, onstage bands, spectacular costumes and themes of culture clash, exhibited many of the features on which the popularity of grand opera would be based.