A formal dance composition either standing on its own or inserted as a diversion in an opera, ballet flourished in France as nowhere else. Even today, the vocabulary of dance steps is predominantly French. When the Italian Lulli came to France and became Lully, he was shrewd enough to alter the models of Italian-type opera into a more Frenchified counterpart by adding a copious amount of dance music. In the 18th-century, ballet spread to Italian, or Italianate, opera as well; even the serious “reform” operas of Gluck contained ballet episodes; so did Mozart’s “Idomeneo,” which was inspired by the Gluck model.

Ballet continued its important role in the 19th century, but in the Romantic era it achieved consideration by composers as a unified dramatic form independent of opera.  This was accomplished with great success by the Frenchmen, Delibes and the Russian, Tchaikovsky.  Dramatic expression was achieved by the music and its corresponding dance, which was performed by soloists and ensembles, serving the same purpose as the vocal solo and chorus in opera.

Instrumental music written for the ballet continued into the 20th century in a form that was much more concise than its predecessors, and in a form that was much more abstract than the set of closed dances that made up the classical ballet.  Most of the ballets of the 20th century were in one act, with one or more scenes.  The music rarely consisted of set dances but was rather in the form of a highly rhythmic symphonic tone poem, interpreted by the dancers in appropriate pantomime and dance gestures.  In modern dance the stylized figures of the dancers of the classical tradition gave way to free gestures and movements, symbolizing the drama in collaboration with the musical symbolism of the orchestral score.  Dance was one of the most successful vehicles for presenting modern music to a receptive public.  In the United States it was the most successful form of dramatic music.  Dance music constituted one of the most frequently heard forms in orchestral concert programs because the music could be presented in its entirety or in suites made up of selected scenes from the score.