According to Duke Ellington in his 1973 autobiography, he wrote Harlem in the summer of 1950 while he was aboard the Isle de France returning from Europe. He writes that it had been commissioned by the NBC Symphony Orchestra “during the time when Maestro Arturo Toscanini was its conductor.”
Just when or if the NBC Symphony Orchestra ever played Harlem is still in question. Recently Professor Donald C. Meyer of the Lake Forest College music department found a 1951 New York Times story about a benefit concert in New York in which some 70 members of this orchestra plus the Ellington orchestra together played it, with Ellington conducting. The Ellington orchestra had previously played it in 1951, and recorded it live in Stockholm, Sweden for release in 1955.
Stanley Slome, former secretary of the Duke Ellington Society Los Angeles chapter, has chronicled various orchestrations and performances in the 1950s, though some mysteries remain. However, the version performed by the Humboldt Symphony and Jazz Orchestra was orchestrated by Luther Henderson and Maurice Peress.
In his liner notes to a 1989 CD, Peress writes “Duke, a master title-giver, described the work as a concerto grosso for jazz band and symphony orchestra... It is one completely integrated movement, the first part of which is held together by the word "Har-lem" (a minor third), intoned by the growl trumpet. The second half is built out of the street funeral dirge (Duke refers to an Elks Band) which begins as an eight-bar blues for three marvelously interwoven clarinets and builds to a climax combining both thematic ideas.”
According to Peress, Ellington described Harlem in this way:
"...The piece of music goes like this (1) Pronouncing the word "Harlem," itemizing its many facets---from downtown to uptown, true and false; (2) 110th Street, heading north through the Spanish neighborhood; (3) Intersection further uptown--cats shucking and stiffing; (4) Upbeat parade; (5) Jazz spoken in a thousand languages (6) Floor show; (7) Girls out of step, but kicking like crazy; (8) Fanfare for Sunday; (9) On the way to church; (10) Church---we're even represented in Congress by our man of the church; (11) The sermon; (12) Funeral; (13) Counterpoint of tears; (14) Chic chick; (15) Stopping traffic; (16) After church promendade; (17) Agreement a cappella; (18) Civil Rights demandments; (19) March onward and upward; (20) Summary--contributions coda.