Name of the Duke Ellington orchestra while recording for Okeh. They were The Jungle Band for Brunswick and Duke Ellington & his Cotton Club Orchestra for Victor. That's when it hit. Three versions with three different line-ups. Original title: Dreamy Blues. Theme: Barney Bigard, lyrics: Mitchell Parish, credits: Irving Mills (Parish stood on his pay roll). This sort of arrangements enabled Duke Ellington to free jazz from its dance function. Some elements might as well come from Ravel or Stravinsky. There's a similar muted trumpet and trombone at the beginning of part two of Le Sacre du printemps.
Frank Sinatra [on In The Wee Small Hours]
Louis Armstrong [with Duke]
Lenny Carlson [with Ry Cooder]
John Barry [in film The Cotton Club]
Asked what Mood Indigo means, Ellington once clarified it's the story of a boy and a girl, loving each other without even knowing it.