Blowhard, Esq. writes:

Ralph Peer — record producer, recording engineer, and talent scout — is one of the most influential men in the history of American music. Not only did he supervise the recording of Mamie Smith’s “Crazy Blues,” the song credited with kicking off America’s blue craze, he discovered Jimmie Rodgers and the Carter Family, two of the most important acts in the history of country music AND he signed Louis Armstrong to his first record deal as bandleader, a contract that produced the legendary Hot Fives and Sevens. Despite these accomplishments, Peer never cared for blues, jazz, or country music, dismissing them as “hillbilly and nigger stuff.”

This song, recorded in Los Angeles in 1930, is the result of a session put together by Peer when he was producing country songs for Victor Records. Jimmie Rodgers, the father of country music, is backed up by Louis Armstrong, the father of jazz, on trumpet and Armstrong’s wife Lil on piano (Louis was estranged from Lil at the time and it would be the last record they made together). In Pops, his Armstrong biography, Terry Teachout writes:

Neither Armstrong is credited on the label of “Blue Yodel No. 9,” but their joint presence is unmistakable. Louis fires off a no-nonsense introduction, and Lil supports him in her best barrelhouse style. Then Rogers enters, telling one his timeless tales of romantic mischance, complete with yodeling. The accent may be of a hillbilly from Mississippi, but the sensibility is straight out of Storyville [the infamous New Orleans slum where Armstrong was born and raised], and Armstrong backs up Rodgers with the same downhome fills he had supplied for Bessie Smith and Ma Rainey. like other country-blues singers, Rodgers freely dropped and inserted beats at will: the last stanza of “Blue Yodel No. 9” consists of three bars in 4/4 time, a bar of 2/4, two more bars of 4/4, and another 2/4 bar, after which the singer continues to switch unpredictably between two and four. But the Armstrongs followed him without too much difficulty, and the resulting performance was far more than a cross-cultural novelty. Not that Louis’s ability to adapt to Rodger’s style should have come as a surprise: the record collection with which he traveled in later years contained everything from Bix [Beiderbecke] and Bing [Crosby] to Bartók’s Concerto for Orchestra. In 1970 he would startle his purist fans by recording an album of country songs. “No change for me, daddy, I was doing the same kind of work forty years ago,” he blithely told a friend.

One thing that Teachout overlooks is that Rodgers’s yodeling, as explained by Nick Tosches in Where Dead Voices Gather, can be traced to the influence of the minstrel singer Emmett Miller. So, in one performance, two of American music’s most important figures combine four strands — minstrelsy, jazz, blues, and country — into one remarkable song.