////I guess my definition of swing is jazz that you can dance to, and that it's growth in popularity, although not it's invention,was tied to the dances that were done by young whites and blacks from 1900 or so on. I would think that before WWI young whites would have primarily known about vaudeville music, but after WWI swing became the R&R of its time, as young whites had more ability to get out to hear music and buy records. Up until the '50's it was common for young people to drop in and out of high school to earn money for the family, but I'm sure some of that went for their entertainment too. Various dance crazes came and went during this period, as with line dancing in our era, but swing kept going too, until R&R lowered the bar.
Chris
ps - there are podcasts of Ian Whitcomb's internet shows that play a lot of pre-WWII music.////

Thanks. I listen to Whitcomb a fair amount and I do enjoy his stuff. In fact, I base my version of "I Aint' Got Nobody" on his and Emmett Miller's for a nice different take. Whitcomb is more restrained vocally than Miller so it's an interesting balancing act. In fact, I got big applause for it last night performing on a uke.

Swing was definitely around before WW1 and before jazz. One guy who is horribly neglected in the histories of the evolution of swing is Al Jolson. Jolson is the ONLY singer in the 1910s whom I have actually heard swinging. He could swing so forcefully that he made the bands behind him start swinging to keep up even when it was apparent that the musicians had no real prior knowledge of experience of doing it. Jolson may be the single most important influence of the emergence of vocal jazz.

As far as bands go, Wilbur Sweatman was an early swing bandleader. I have stuff of his on digital as well as vinyl (on Columbia Graphophone, if I remember correctly) from the 10s and it was swinging in a fashion no other was until the Original Dixieland Jass Band started recording in 1917. Unfortunately, I don't think Jolson ever sang with Sweatman's band probaby due to segregation. that would have been amazing stuff, no doubt.