Some nice vids for you.
First some Reverend Gary Davis. He played a really clean style of pickin' blues, some almost jazzy ragtime blues, in the 1920s, and later on into the 1970s. It's simple; it's clean like cold water. He's on a guitar here, but he played jazz banjo too.
Next, Django Reinhardt, Beyond the Sea. I think it's his most beautiful work, and that's saying something. He is the most groundbreaking guitarist / banjo player most of you have probably never heard of. His life was an utter tragedy, but damn, could he play. The reason he survived WWII - he was a Gypsy in Paris and most of the Gypsies were murdered by the Nazis - is that he and some fellow musicians were under the protection of a Luftwaffe officer who loved jazz. Whatever happened to the Nazi who saved the gypsy jazz virtuosos? This is what happened to him. I feel like Paul Harvey now. Good day. Reinhardt's style was more highly developed than Reverend Gary Davis' style, and clearly influenced by the celtic music touch of the Romani, the Gypsies, just as blues and bluegrass were influenced by the celtic music touch of our Scots-Irish rural white fiddlers. But you can almost see the interplay between different genres of music. The chords and notes are almost layered together, and there's more than a touch of swing in his bluesy jazz. Reinhardt was a tremendous admirer of Charlie Parker and Miles Davis. Did they influence him? Did he influence them? Probably.
That's not the only way jazzy blues went. Some of it co-opted traditional blues songs, and traditional bluesmen. Check out this version of the Mojo Workin' Blues, with Muddy Waters and Sonny Boy Williams. Yes, that's Matt "Guitar" Murphy on the guitar, playing a traditional blues lick the way it might have been played in 1925 - clean, straight, right on the notes and right with the beat. It's an unusual take on the song. A good one. It works.
At the same time, some jazzy blues went very, very jazzy. Check this out with Willie Dixon, T-Bone Walker, and Memphis Slim.
Are you seeing how raw old blues morphed into kinda jazzy blues? It wasn't a clean break, and I've only picked a small selection of players who were there at the revolution, or the evolution anyhow. Django Reinhardt was a pivot point in that; if he wasn't the pivot, then he was at least standing on it, along with Charlie Parker and Miles Davis ("Birth of the Cool"). If you listen to Memphis Slim's jump blues piano playing below, you can see the skeleton of what later became cool jazz, or at least the piano part of it. Slow Memphis Slim down a little bit, and you get George Russell's jazz piano.
You want to hear blues morph into jazz in ten seconds? Check out Matt "Guitar" Murphy here. Mid-song, he plays something Django might have played. Then he goes right back into jump blues. You hear it evolve; it's like watching a primeval salamander turn into a lizard. Pretty cool. BTW, Murphy is the guy who played Aretha Franklin's husband, the diner cook, in The Blues Brothers. Y'know, just in case you were wondering whether you should know who he is.
So that was history, and a pastiche part of how the American born blues and jazz music got from juke joints to Carnegie Hall, and super-sophisticated jazz musicians in suits and black turtlenecks. But what ever happened to swingy, virtuoso-style, roots bluesy banjo jazz? Why don't you ask Bela Fleck.
It didn't die off. It's still with us. Does that Bela Fleck piece sound derivative, in a very good way? I think it does. Culture doesn't happen in a vacuum.