Based on comments in various Debussy letters and in Léon Vallas's biography,[1] it has generally been assumed that composition of the Nocturnes began in 1892 under the title Trois Scènes au Crépuscule ("Three Scenes at Twilight"),[2] an orchestral triptych.

[1] Trois Scènes au Crépuscule was inspired by ten poems by Henri de Régnier entitled Poèmes anciens et romanesques (published in 1890).

[10] He was also working on another orchestral triptych after a cycle of three poems by another symbolist poet, Stéphane Mallarmé, called L'après-midi d'un faune, that was more in keeping with the new style of music and inspiration Debussy was seeking.

He had in fact asked Henri de Régnier, a close associate of Mallarmé, to inform the latter of his interest in setting the poems to a new kind of musical impression.

[13] Debussy was impressed and flattered by Ysaÿe's interest in his music and decided to rewrite his Twilight Scenes into a piece for solo violin and orchestra.

[2]In 1894, after completing the first movement of his Mallarmé triptych entitled Prélude (to "The Afternoon of a Faun"), he began the recomposition of the Twilight Scenes in a new inspired style, retitling the new version Nocturnes after a series of paintings of the same name by James McNeill Whistler, who was living in Paris at the time.

[10] Following the abandonment of Rodrigue et Chimène in 1893, Debussy had immediately begun work on an opera more to his liking, Pelléas et Mélisande, which occupied him with no small measure of trouble over the next nine years, until it premiered on 30 April 1902.

"[2][18] For several years after its publication, almost until the day he died, Debussy continued to tinker with the composition, at first making corrections to dozens of errors in his copy of the published score, then moving on to adjusting small passages and fundamentally revising the orchestration.

"[19][1] Debussy continued to modify the composition just as he had for the seven years prior to its publication, sometimes just not satisfied or sometimes thinking of a new experiment in sound, a new color combination of instrumental timbres he hadn't heard yet.

[21] One reviewer states "in this new critical edition for the Debussy oeuvres complètes, all of the most important questions concerning the establishment of a text of the Nocturnes for practical performance have been confidently answered.

[14] Debussy wrote an "introductory note" to the Nocturnes and each of the individual movements, printed in the programme for the first complete performance in 1901:[22] "The title 'Nocturnes' is to be interpreted here in a general and, more particularly, in a decorative sense.

According to Debussy, "'Nuages' renders the immutable aspect of the sky and the slow, solemn motion of the clouds, fading away in grey tones lightly tinged with white.

"[10] Biographer Léon Vallas recorded Debussy's comments on the genesis of this piece: One day, in stormy weather, as Debussy was crossing the Pont de la Concorde in Paris with his friend Paul Poujaud, he told him that on a similar kind of day the idea of the symphonic work "Clouds" had occurred to him: he had visualized those very thunderclouds swept along by a stormy wind; a boat passing, with its horn sounding.

[10]Léon Vallas, in his biography, continues: Debussy went on to explain to Poujaud that "Festivals" had been inspired by a recollection of merry-making in the Bois de Boulogne, with noisy crowds watching the drum and bugle corps of the Garde Nationale pass in parade.

"[23] According to Debussy, "'Sirènes' depicts the sea and its countless rhythms and presently, amongst the waves silvered by the moonlight, is heard the mysterious song of the Sirens as they laugh and pass on.