Fauré was born in Pamiers, Ariège, Midi-Pyrénées, in the south of France, the fifth son and youngest of six children of Toussaint-Honoré Fauré (1810–85) and Marie-Antoinette-Hélène Lalène-Laprade (1809–87). According to the biographer Jean-Michel Nectoux, the Fauré family (pronounced "Faoure" in the occitan local dialect) dates to the 13th century in that part of France. The family had at one time been substantial landowners, but by the 19th century its means were reduced. The composer's paternal grandfather, Gabriel, was a butcher whose son became a schoolmaster. In 1829 Fauré's parents married. His mother was the daughter of a minor member of the nobility. He was the only one of the six children to display musical talent; his four brothers pursued careers in journalism, politics, the army and the civil service, and his sister had a traditional life as the wife of a public servant.

When Fauré was born, Berlioz and Chopin were still composing; the latter was among Fauré’s early influences. In his later years Fauré developed compositional techniques that foreshadowed the atonal music of Schoenberg, and, later still, drew discreetly on the techniques of jazz.[ Duchen writes that early works such as the Cantique de Jean Racine are in the tradition of French nineteenth-century romanticism, yet his late works are as modern as any of the works of his pupils. By using unresolved mild discords and colouristic effects, Fauré anticipated the techniques of Impressionist composers.
 

In contrast with his harmonic and melodic style, which pushed the bounds for his time, Fauré's rhythmic motives tended to be subtle and repetitive, with little to break the flow of the line, although he used discreet syncopations, similar to those found in Brahms's works. Copland referred to him as "the Brahms of France".
 

Fauré is regarded as one of the masters of the French art song, or mélodie. Ravel wrote in 1922 that Fauré had saved French music from the dominance of the German Lied. Two years later the critic Samuel Langford wrote of Fauré, "More surely almost than any writer in the world he commanded the faculty to create a song all of a piece, and with a sustained intensity of mood which made it like a single thought". 
 

In Copland's view the early songs were written in the 1860s and 1870s under the influence of Gounod, and except for isolated songs such as "Après un rêve" or "Au bord de l'eau" there is little sign of the artist to come. With the second volume of the sixty collected songs written during the next two decades, Copland judged, came the first mature examples of "the real Fauré". He instanced "Les berceaux", "Les roses d'Ispahan" and especially "Clair de lune" as "so beautiful, so perfect, that they have even penetrated to America", and drew attention to less well known mélodies such as "Le secret", "Nocturne", and "Les présents". Fauré also composed a number of song cycles. Cinq mélodies "de Venise", Op. 58 (1891), was described by Fauré as a novel kind of song suite, in its use of musical themes recurring over the cycle. For the later cycle La bonne chanson, Op. 61 (1894), there were five such themes, according to Fauré. He also wrote that La bonne chanson was his most spontaneous composition, with Emma Bardac singing back to him each day's newly written material.
 

The Requiem, Op. 48, was not composed to the memory of a specific person but, in Fauré's words, "for the pleasure of it." It was first performed in 1888. It has been described as "a lullaby of death" because of its predominantly gentle tone. Fauré omitted the Dies Irae, though reference to the day of judgment appears in the Libera me, which, like Verdi, he added to the normal liturgical text. Fauré revised the Requiem over the years, and a number of different performing versions are now in use, from the earliest, for small forces, to the final revision with full orchestra.
 

Fauré's operas have not found a place in the regular repertoire. Prométhée is the more neglected of the two, with only a handful of performances in more than a century. Copland considered Pénélope (1913) a fascinating work, and one of the best operas written since Wagner; he noted, however, that the music is, as a whole, "distinctly non-theatrical." The work uses leitmotifs, and the two main roles call for voices of heroic quality, but these are the only ways in which the work is Wagnerian. In Fauré's late style, "tonality is stretched hard, without breaking." On the rare occasions when the piece has been staged, critical opinion has generally praised the musical quality of the score, but has varied as to the dramatic effectiveness of the work. When the opera was first presented in London in 1970, in a student production by the Royal Academy of Music, Peter Heyworth wrote, "A score that offers rich rewards to an attentive ear can none the less fail to cut much ice in the theatre. ... Most of the music is too recessive to be theatrically effective." However, after a 2006 production at the Wexford Festival, Ian Fox wrote, "Fauré's Pénélope is a true rarity, and, although some lovely music was anticipated, it was a surprise how sure the composer's theatrical touch was."