Claude Debussy (1862-1918) was one of the most important composers leading into the 20th century. He pushed against boundaries, created his own harmonies, and paved the way for future composers to compose beautiful and unique sounds. Read more about him here.
Nuages is the first movement of a work called Nocturnes , a set of three symphonic poems (a symphonic poem is a work that illustrates a poem, painting, etc.), written around 1897 and premiered in December, 1900 (read more about the work here). At first listening, Nuages is light and shimmery, but there is much going on musically. The opening theme introduced by the woodwinds is developed and varied throughout the work, and a gorgeous 2nd theme appears in the flute and harp and alternates with a solo violin/viola duet (4:52-6:10). Fun fact: the English horn has a very unique role in Nuages. It plays the same 5 note pattern all the way through with extremely little variation (the first rendition is 0:20-0:34).
So what does it all mean? First of all, Nuages is French for “clouds.” With that interpretation in mind, this piece is full of imagery. The opening theme can represent ever-shifting clouds as they move through the sky. Parallel triads changing tonalities and constantly shifting and then holding a C major chord where the French horn interjects softly with an E (2:12-2:30) is a ray of sunlight peaking through the cloud covering. (I’d also like to point out that the E played by the horns here is the pivot note into the next section, where unison strings create a new melody based on E while the woodwinds build in a counter-rhythm on top.) In the program for the concert where Nuages was premiered, Debussy wrote that his intent for this piece was to capture “the unchanging appearance of the sky with the slow and melancholy progress of the clouds, ending in a gray dissolution gently tinged with white”.