‘Louis Armstrong, Master of Modernism’, by Thomas Brothers

Louis Armstrong, Master of Modernism, by Thomas Brothers, WW Norton, RRP£25/RRP$39.95, 608 pages

Years after the trumpeter Louis Armstrong left New Orleans for Chicago in 1922, he recalled how lucky he was to have travelled alongside a family friend who was carrying an overflowing basket of fried chicken. Trains in the South didn’t bother laying on dining cars for black passengers, making supplies essential. With such details, Thomas Brothers locates the racially charged backdrop to this highly focused account of a crucial period, the 1920s and early 1930s, in Armstrong’s life.

By 1931 and 1932, Armstrong’s recordings outsold those of every other performer in America, regardless of genre or colour. In an engrossing follow-up to Louis Armstrong’s New Orleans (2006), Brothers, professor of music at Duke University, sets out in near-forensic fashion to explain the full import of Armstrong’s musical and political achievements.

Master of Modernism starts with Armstrong on that train to Chicago to join King Oliver’s Creole Jazz Band as second cornetist. The audiences he plays to are largely black, yet a small group of awestruck white musicians gathers round the stage, some notating what they hear on their shirt cuffs. The band call them “the alligators”.

“The astonishing thing about Armstrong,” writes Brothers, “is that he invented not one but two modern art forms, one after the other, both immensely successful and influential, and that he did this with vigorous commitment to means of expression derived from the black vernacular he had grown up with.”

He was a supreme trumpet virtuoso who laid down the foundations of jazz modernism to black audiences and fixed African-American culture at the centre of the American entertainment industry with his innovative vocals. And, as Brothers shows, Armstrong’s genius both as an instrumentalist and as a singer was matched by his ability to negotiate racial boundaries so acute that a slight miscalculation could have terrible consequences.

Brothers captures the complexities of Armstrong’s world from the outset, with a sketch of a 1931 concert before an all-white audience in Memphis. Billed accurately as “Master of Modernism and Creator of his Own Song Style”, the trumpeter nearly missed the gig, having spent the night in jail after he was spotted on the tour bus sitting next to his manager’s white wife. “Why didn’t you shoot him in the leg?” asked one policeman of a colleague.

Yet after the concert, officers flocked to thank Armstrong for dedicating a song to the Memphis Police Department. They seemed not to have caught lines such as “I’ll be tickled to death when you leave this earth, you dog”. Armstrong’s vocal style, steeped in the codes and cadences of African-American working-class vernacular, was fine-tuned to hide meaning from some while entertaining all.

Brothers shows how these layers of social meaning coursed through Armstrong’s music. A thorough and readable investigation of Armstrong’s recorded output during this period balances technical language with scene-setting context and colourful descriptive passages. One Armstrong “break” (a short, improvised phrase in the music) is described as conveying the feeling that “he is putting his feet up in his Harlem apartment after a stuffy rehearsal, tired of flashy dressers sneering at his clunky shoes”.

But the book works on a much wider level. Armstrong was at the heart of the American entertainment industry in a period when film, radio and recording were maturing fast. Women made a fortune singing the blues, the Harlem Renaissance was in full bloom and the puritanism of prohibition was balanced by the moral licence of the speakeasy. And Armstrong was in the thick of it, whether at the National Association for the Advancement of Colored People’s annual ball – “the pinnacle of posh”, according to one writer – or, about to launch his movie career, checking in to the Dunbar in Los Angeles, then the only hotel west of the Mississippi that accepted African-Americans.

With skin colour an ever-present factor, any understanding of his music must look at broad social relationships and historical processes as well as biographical narrative and music criticism. As Brothers amply demonstrates, even the offensive stereotypes the trumpeter deployed before white audiences were double-edged, albeit heavily coded, and did not betray either Armstrong’s colour or class.

It makes for a rounded, rigorous, vivid portrait of a man who, Brothers argues, became “the ultimate representative of African-American musical history”.

Mike Hobart is the FT’s jazz critic