it's not really true that glen miller was unique
Back in the 20s,30s and 40s Harlem was the cultural capital of the United States. When main stream folks wanted to know what the latest dances were they went 'uptown' to look at the dancers at the Savoy and other joints. It may be fashionable now for others to completely over look that period, but Jimmy Lunceford,Basie, Ellington and Chick Webb were forced to play second fiddle to Goodman, Dorsey Shaw and Miller. It would be nice if everyone bore that in mind. Jazz and its offshoots were essentially the music of black America. They never really got the credit for inventing this most American of music and the same can be said of Rock and Roll, but then I guess that Hollywood played its part in suppressing so much of the cultural offerings of black Americans and so many can be forgiven for not knowing this.
