The legend that he was born on 4 July 1900 was discredited some time ago, but that hasn't stopped the record industry at large from celebrating the 100th birthday of Louis Armstrong (for the record, the true date is 4 August 1901). Armstrong is the irreducible essence of 20th-century music, its daring and newness crystallised in the trumpet playing of a black American who did his most important growing-up in the Colored Waifs' Home in New Orleans. There, he was given a trumpet, which, by 1918, he had mastered sufficiently to be scaring every other musician in town. His progress says much about the creative spirit, as well as a more melancholy truth: that genius, usually, has no place useful to go.
Armstrong didn't make his first records until 1923 - the American record industry was unhappily slow in recording some of the early black groups - and, even then, it was as second-cornet player in the King Oliver Jazz Band. Hidden in their musty recordings, he makes a bright but hardly immortal impression. But when Armstrong arrived in New York in 1924 and joined Fletcher Henderson's smart band, it was like a typhoon blowing into the music of that city. His records with Henderson are often astounding. The band were still comparatively stiff, and hardly what anyone would now recognise as a jazz group; but when Armstrong gets space and plays a solo, he electrifies the air. The old acoustic recordings seem to rattle with his intensity. A year later in Chicago, he began making the small-group sessions that came to be known as the Hot Fives and Hot Sevens (being re-issued in a handsome and impeccably remastered set by Sony Jazz). As the discs circulated in America and then filtered around the world, music began to change. All the stirrings that had been felt in American music suddenly came into focus in Armstrong's work: not only in his trumpet playing, which created one dazzling, mercurial statement after another, but also in his singing, which almost casually set the insouciant tone of every jazz and popular singer who came after him, and in the sheer charismatic brio of his being there, in a recording studio. You could feel his presence as the music poured out of wind-up gramophones around the world. He loosened the stays on popular song. After Armstrong, music was faster, sharper and less bound by rules.
The music of those records - the Hot Fives and Hot Sevens lasted until 1928, when Armstrong began recording in front of larger orchestras - is still dumbfounding. The earlier recordings have a knockabout feel to them, of a young master finding his way, but, by 1927, when Armstrong was reeling off one masterpiece after another, the group had a majestic sensitivity conferred on it, the surrounding sounds falling inevitably into place around Armstrong's trumpet. If anything, the primitive recording heightens the impact of his playing: unvarnished by modern effects, all one hears is the spontaneous grandeur of his imagination. The three minutes of "Tight Like This", recorded at one of the last Hot Five sessions, still seem like an unrepeatable outburst, a crack in sound and space that refuses to be papered over by the passage of time.
Inevitably, it was a progress that Armstrong couldn't sustain. "Almost since leaving Oliver, he had been operating as a vaudevillian," Max Harrison later wrote, and it was hard to see where this quicksilver talent could have gone. Until Charlie Parker came along, jazz had no pretensions to art, or even to music for music's sake. Armstrong was a working entertainer whose principal activity lay in touring American theatres. In the Thirties, he worked mostly as a frontman for an orchestra, and fell prey to the ridiculous material that the record industry offered him. Armstrong had no aspirations to compose or lead the kind of band that Duke Ellington helmed and, before long, he found the music passing him by. He was one of the few blacks to appear in mainstream Hollywood films - but even then, it was usually in a demeaning guest-star role. By the Forties, with bebop fermenting in the wings, Armstrong seemed passe. Brash young men such as Dizzy Gillespie saw him as a white man's nigger, an Uncle Tom debasing the aspirations of the jazz elite. (It is worth remembering Billie Holiday's riposte: "Sure Pops Toms, but he Toms with class.")
So Armstrong went back to a small group: the All Stars, a version of which he led for the rest of his life. In the following decade, he came to be seen as the grand old man of the music, even though he was only in his fifties. There were still great records to come. Wynton Marsalis maintains that some of Armstrong's most characterful work is in his later recordings, where the regal sound is distilled into simple melodic epigrams, standard tunes given a lusty existence in his declamatory phrasing. Increasingly, Armstrong turned to singing, and most who were born after 1950 probably think of him as a vocalist-entertainer, rather than as a jazz musician. Verve's recent reissue of one of Armstrong's sets with the Russell Garcia Orchestra, I've Got the World on a String, is a disarming listen. The huge, almost primeval voice, cushioned by simpering strings, seems unearthly at first, but the way "Pops" handles the rhythms in each line, the tiny inflections that make the music swing even in this setting, point up his bequest to American music.
He remained a vaudevillian, perhaps: the grinning showman who provoked the distaste of Gillespie preferred to mask his feelings most of the time, the way any black artist trying to succeed in a white world had to in the early part of the 20th century. He kept his own counsel, a canny southerner, with a wry take on some of his country's foibles. Audiences who watched him mugging alongside Barbra Streisand in Hello, Dolly! might have been surprised to be reminded that, a few years earlier, he had openly criticised President Eisenhower's failure to assist in the anti-segregation struggle of 1957, cancelling a state-sponsored tour in protest. The wise old patriarch of "What a Wonderful World" had seen more than enough to know that it wasn't always so wonderful. All who knew Armstrong remember his gracious demea-nour, his warmth towards everyone with whom he came into contact: once he knew his fellow man, he mollified him.
His greatness is routinely acknowledged, but, like all whose most powerful work is distant from our own time, he is beginning to seem remote. The music business in which Armstrong toiled has transformed into an environment where individuals become more like franchises than particular artists. In those now ancient recorded solos, Armstrong asserted an Olympian identity that thrilled and galvanised his culture, and started something unstoppable. And every time you hear him, that momentous presence seems to grow large and alive once again.
The Complete Hot Five and Hot Seven Recordings, a set of four CDs and 84-page hardback book, is released by Sony Jazz on 4 September. Ambassador Satch, Satch Plays Fats and Satchmo the Great have just been released by Sony Jazz. I've Got the World on a String is available on Verve