Candide is an operetta with music composed by Leonard Bernstein and lyrics primarily by the poet Richard Wilbur, based on the 1759 novella of the same name by Voltaire. Other contributors to the text were John Latouche, Dorothy Parker, Lillian Hellman, Stephen Sondheim, John Mauceri, John Wells, and Bernstein himself. Maurice Peress and Hershy Kay contributed orchestrations.

The operetta was first performed in 1956 with a libretto by Lillian Hellman, but since 1974 it has been generally performed with a book by Hugh Wheeler, which is more faithful to Voltaire's novella. Although unsuccessful at its premiere, Candide has overcome the unenthusiastic reaction of early audiences and critics, and achieved more popularity.

Candide was originally conceived by Lillian Hellman as a play with incidental music in the style of her previous work, The Lark. Bernstein, however, was so excited about this idea that he convinced Hellman to do it as a "comic operetta"; she then wrote the original libretto for the operetta. Many lyricists worked on the show: first James Agee (whose work was ultimately not used), then Dorothy Parker, John Latouche and Richard Wilbur. In addition, the lyrics to "I Am Easily Assimilated" were done by Leonard and Felicia Bernstein, and Hellman wrote the words to "Eldorado". Hershy Kay orchestrated all but the overture, which Bernstein did himself.

Candide first opened on Broadway as a musical on December 1, 1956, at the Martin Beck Theatre. The premiere production was directed by Tyrone Guthrie and conducted by Samuel Krachmalnick. The sets and costumes were designed by Oliver Smith and Irene Sharaff, respectively. It was choreographed by Anna Sokolow. It featured Robert Rounseville as Candide, Barbara Cook as Cunegonde, Max Adrian as Dr. Pangloss, and Irra Petina as the Old Lady. This production was a box office disaster, running only two months for a total of 73 performances. Hellman's libretto was criticized in The New York Times as being too serious:

When Voltaire is ironic and bland, [Hellman] is explicit and vigorous. When he makes lightning, rapier thrusts, she provides body blows. Where he is diabolical, [she] is humanitarian ... the libretto ... seems too serious for the verve and mocking lyricism of Leonard Bernstein's score which, without being strictly 18th century, maintains, with its gay pastiche of past styles and forms, a period quality.

The first London production debuted at the Saville Theatre on Shaftesbury Avenue on 30 April 1959 (after playing for a short time at the New Theatre Oxford and the Manchester Opera House). This production used Lillian Hellman's book with an additional credit 'assisted by Michael Stewart', and it was directed by Robert Lewis with choreography by Jack Cole. The cast included Denis Quilley as Candide, Mary Costa as Cunegonde, Laurence Naismith as Dr. Pangloss and Edith Coates as the Old Lady. The musical director was Alexander Faris.

Without Bernstein's involvement, the show underwent a series of Broadway revivals under the direction of Harold Prince.^[when?] Lillian Hellman, the author of the original book, refused to let any of her work be used in the revival, so Prince commissioned a new, one-act book from Hugh Wheeler. The sole element of Hellman's book that remained was her invented name (Maximilian) for Cunegonde's brother. (The character has no given name in Voltaire's novella, and is referred to as "Cunegonde's brother" or "the young Baron".)^{[citation needed]}

The lyrics were worked on by the team of artists listed above. This 105-minute version, omitting over half of the musical numbers, was known as the "Chelsea version", and opened in 1973 at Robert Kalfin's Chelsea Theater Center in the Brooklyn Academy of Music, before moving to the Broadway Theatre in 1974 and running there for nearly two years, closing in 1976 after 740 performances. The 1974 Broadway revival starred Mark Baker (Candide), Maureen Brennan (Cunegonde), Sam Freed (Maximilian), Lewis J. Stadlen (Dr. Pangloss), and June Gable as the Old Lady.