Its defiantly much broader in a big way. All the way from scat in the late 1920s, to bebop in the 1950s, and all the way to hip hop and rappers.
Here is a link that will explain it much better than I can. Ive only caught notice of scat around a year ago, so I am far from being an expert on the subject. The link below can give you more information than I personally can. I hope it contains what your wanting to know.
Scat singing - Wikipedia, the free encyclopedia