Pop goes the music.

Serge Diaghilev considered Offenbach too vulgar for ballet, or possibly the cancan king was just not chic enough at the time. Constant Lambert was never able to persuade anyone to stage a ballet to Sousa music, and even Strauss's Viennese waltzes were at one time regarded as a little downscale for the noble art of Terpsichore.

So when did pop music first appear on the lordly stages of theatrical dance? Well, earlier than you might have thought, earlier perhaps than even the snobbish but always knowledgeable Diaghilev might have realized. For in the original 1789 Dauberval version of La Fille Mal Gardee, the music was exclusively provided from popular French songs of the day. This was later tarted up by various composers, but even in the John Lanchbery version of the score choreographed by Ashton, it seems that there are still a few vestigial melodies hanging over from that very first production in Bordeaux.

And, of course, popular music found its way onto the ballet stage, even in Diaghilev's day, through composers as varied as Stravinsky in Petrouchka and Poulenc in Les Biches, using snatches of popular song almost as local color. But it is in recent years that pop music has really made its presence felt in modern choreography. When, how, and why? Let's discuss it, but not always in that order. Still, at least let's try to start with when.

A popular element entered dance during ballet's early Americana stage. Aaron copland's score for Billy the Kid in 1938 used certain cowboy and Mexican tunes, as did his Rodeo four years later. And there were those pop composers who became interested in ballet: cole Porter's Within the Quota was composed for Jean Borlin's Ballets Suedois as early as 1923, and had a story and decor by Gerald Murphy (the one whose law was "living well is the best revenge"). Murphy, coincidentally enough, also helped inspire Richard Rodger's 1939 excursion into ballet with the Ballet Russe de Monte Carlo's Ghost Town, which had choreography by Marc Platoff (Marc Platt) and included Algernon C. Swinburne among its unlikely cast of characters.

Of course, as with Gershwin's Rhapsody in Blue (1924) and An American in Paris (1928), neither actually written for ballet, even though both have frequently been choreographed, these Porter and Rodgers works were symphonically styled compositions, although a contemporary commentator on Ghost Town referred to it as "fair musical-comedy music striking quite the wrong note at the Metropolitan Opera House."

As far as I can tell the first modern breakthrough in the use of genuine pop music for ballet came in 1940, when again Ballet Russe de Monte Carlo, by then embarked on a wholesale program of American acclimatization, offered Leonide Massine's The New Yorker. Based thinly on characters from New Yorker cartoons, the score was chiefly orchestrations of "classical" Gershwin, but, bingo! Here comes the breakthrough: it did include variations on "I Got Rhythm." And could Ethel Merman have asked for anything more?

As jazz dance made its presence increasingly felt theatrically throughout the forties, fifties, and sixties, many choreographers, such as Alvin Ailey and Anna Sokolow, started to use jazz, swing, and the blues, while in classic ballet a major step was taken in 1970, when George Balanchine, like Massine before him, also got rhythm and staged Who Cares? to Gershwin music. This was buttressed by an enormously lengthy and erudite program note by Lincoln Kirstein, obviously someone who cared a great deal that the music choice would not be misinterpreted or misunderstood: he described George and brother Ira as "aristocrats of Anmerican lyricism, masters of music to the American electorate."

Rock music, live rock music, actually, had already made its ballet appearance with Gerald Arpino's Trinity as early as 1971, while in 1974 Kenneth MacMillan had livened up the Royal Ballet repertoire with Elite Syncopations to rags by Scott Joplin and others.

Serious dance had obviously found a new musical constituency, and the main reason for this was surely to be found in the post-Schoenberg era of classical music. Serialism, and everything that came after in music, was not generally accessible to large audiences, and composers were not writing stuff like Tchaikovsky anymore. Choreographers selecting more pop-style forms were able to remain both contemporary and yet use scores that had the ear of an enormous public.

But, as Mr. Jolson used to say, "you ain't heard nuthin' yet," and in a sense we hadn't. I suppose it was Twyla Tharp, with her uncanny yet instinctive sense of the zeitgeist, who knew what to do next. We were living in a world layered with revisionism, deconstruction, and recycling, yet cushioned with simple nostalgia. In 1973, Tharp and the Joffrey Ballet made cutting-edge history with Deuce coupe, a ballet not merely to pop music, but using actual recordings by pop artists (in this case the Beach Boys). As with Massine's The New Yorker, thirty-three years earlier, bingo! Something new had happened.

So soon we had Tharp herself choreographing to Frank Sinatra, Paul Taylor collaborating in absentia with the Andrews Sisters, the Joffrey staging a whole evening (not to mention an economic recovery) to recordings by Prince, and, most recently of all, a Lar Lubovitch work to unlikely grungelike recordings of Cole Porter. And, I suspect, we have only just considered the tip of the iceberg. The choreography lends cultural respectability and even (were any nowadays required) intellectual validity to the music, and the music offers a readily acceptable and extremely attractive base for the choreography.

It doesn't matter, of course, for intrinsically there may well be only two kinds of music, good and bad. Still, it would be a brave man who suggested that those songs sung by Sinatra offered the same intellectual and even emotional challenges as, say, late Beethoven string quartets. I am not, I hope, being snobbish about this. Many people are tentatively suggesting that elitism has its place in the arts, but personally I question whether the arts can maintain any place without elitism.

And I cannot help wondering, now that dance is going pop so emphatically and audiences are responding enthusiastically to Billboards or Nine Sinatra Songs, how much of that response is evoked by the choreography, which is the intrinsic value of the ballet itself, and how much by Prince and Sinatra, and the pleasurable permission they offer to let audiences enjoy what they truly enjoy, and all in the hallowed name of high art. It's a thought.