I recently started collecting Boogie Woogie tracks off of YouTube and learned some interesting stuff along the way.
I started out thinking about BW as being some early form of rock and got excited about finding songs from 1930's and earlier that had BW traits, thinking they were extraordinary gems. Then I found out (see Wikipedia for this) that BW goes back to even before the twenties, and indeed, is as old as jazz itself.
Next I learned that BW became kind of a cultural virus around 1947, and virtually everyone was recording at least one BW song. Almost every song from that period has 'Boogie' in the title, usually "XXX's Boogie". All the hitmakers of the day have BW songs, Woody Herman, Count Basie, Tommy Dorsey, etc. Check out YouTube and you'll find scores of BW playlists.
But it gets more interesting than that. BW began in east Texas logging camps and developed organically with the expansion of railroad. Ground zero was (is) Marshall, TX, where they celebrate that heritage to this day. BW style in Marshall remained unchanged, but at each train stop (logging camp) the style became more evolved. You could estimate the distance from Marshall by how evolved the BW style sounded in the bar you were in. BW pianists spent their years traveling from camp to camp on the RR. And to state the obvious, sonically, BW reflected the sound of the engines and clatter of trains.
Pinning down the beginning of rock is nigh impossible. For some odd reason there are people who want to say that Ike Turner's 'Rocket 88' is the first rock song, apparently due more to its popularity than its innovation. Infectious dance beat and riotous swing? Hell, the very earliest BW of the 20's has that. Sexual suggestivity? BW lyrics sometimes exhort the women to shake their asses. Did BW walking basslines get replaced with something else? Nope, early rock by Elvis still has standard BW basslines. Electric guitars? Now you're talking. I would say that the earliest BW having an electric guitar is a good candidate for pioneer rock. That brings Western Swing (Bob Wills, Spade Cooley) into the fold.
The most insightful statement I've ever heard about the origins of Rock was by Robbie Robertson of The Band, in the film The Last Waltz. It's country...it's Louisiana gumbo and Cajun...it's blues...all of it. It's genesis was in religious revival meetings and county fairs, where late into the night after the community leaders had gone home, you'd have musicians throwing these styles all together in unorthodox ways, and doing crazy stage antics (e.g. Chuck Berry's duck walk).
Something I love in the earliest rock is a particular sonic quality in the rhythm section that I call the Washing Machine. The recipe seems to be double bass (acoustic), piano and drums with brush sticks. When they're playing really tight, the three fuse into a single rhythm-machine timbre. A wacky, anthropomorphized Washing Machine drawn by R. Crumb comes to mind. You hear it on a lot of early Elvis tracks.