The tune was composed for a radio broadcast in October 1930 and was originally titled "Dreamy Blues." It was "the first tune I ever wrote specially for microphone transmission," Ellington recalled. "The next day wads of mail came in raving about the new tune, so Irving Mills put a lyric to it." Renamed "Mood Indigo," it became a jazz standard.
The main theme was provided by Bigard, who learned it in New Orleans, Louisiana from his clarinet teacher Lorenzo Tio, who called it a "Mexican Blues". Ellington's distinctive arrangement was first recorded by his band for Brunswick Records (Cat No. 01068) on 17 October 1930. It was recorded twice more in 1930. These recordings featured Arthur Whetsol (trumpet), Joe Nanton (trombone), Barney Bigard (clarinet), Duke Ellington (piano), Fred Guy (banjo), Wellman Braud (bass), Sonny Greer (drums). An unusual thing about this piece was the way that the Duke blended the muted trumpet, muted trombone and clarinet, to give a unified sound.
What makes the original recording(s) so interesting is the fact that Ellington has taken the traditional front-line of trumpet, trombone and clarinet, and turned them "upside down." At the time of these first three recordings in 1930, the usual voicing of the horns would be clarinet at the top (highest pitch), trumpet in the middle, and the trombone at the bottom (lowest pitch). In "Mood Indigo," Ellington voices the trombone right at the top of the instrument's register, and the clarinet at the very lowest. This was unheard of at the time, and also created (in the studio) a so-called "mike-tone"—an effect generated by the overtones of the clarinet and trombone (which was tightly muted as well). The "mike-tone" gives the audio-illusion of the presence of a fourth "voice," or instrument.
Ellington was to re-employ this effect in "(In My) Solitude" (1932), "Dusk" (1940) and many other pieces throughout his career. The Ellington band performed and recorded the song continuously throughout its 50 years under Duke, both in its original form and as a vehicle for individual soloists. It remains a staple of the Duke Ellington Orchestra.
"Mood Indigo" is performed both as an instrumental and as a vocal. It has been recorded by a countless number of artists, ranging from Charles Mingus to Paul Robeson, Ella Fitzgerald, Dinah Washington, Nina Simone, Joe Sample, Nat "King" Cole, Frank Sinatra, Louie Armstrong, Earl Grant, Joe Jackson, Yukihiro Takahashi, The Georgetown Chimes, and Kelly Hogan.
Film scores 
"Mood Indigo" is featured in the films Paris Blues (1961), The Untouchables (1987), Curtain Call (1999), and The Legend of Bagger Vance (2000), and in the miniseries Mildred Pierce (2011). It is also the closing music for the film The Cotton Club (1984).
See also 
- ASCAP Title Search on author credits
- Hasse, John Edward (1995). Beyond Category: The Life and Genius of Duke Ellington. Da Capo Press. p. 134. ISBN 0-306-80614-2. Retrieved 1 September 2010.
- Holden, Stephen (1987-02-01). "Theater; Mitchell Parish: A Way With Words". New York Times