It was Harlem in Heavenly Houston: Club Matinee - "the Cotton Club of the South" - was right around the corner, and right down the street from that was Duke-Peacock Records, before Motown the most important black-owned record company in America.
In Sig Byrd's Houston, the eponymous mid-century chronicler of Houston's beautiful losers and no-'count boozers devoted an entire chapter to Pearl Harbor. Much of it focused on a scuffling, obscure R&B singer who wanted to join the ranks of "all the other Fifth Ward boys who had functioned right and gone high in the world of boogie, jive, and bop: Illinois Jacquet, Gatemouth Brown, Arnett Cobb, Goree Carter, and Ivory Joe Hunter."
Byrd didn't use the term "rock and roll" because it wasn't yet in all that common a parlance in 1955, when his book was published. Fifth Ward boogie kings, jivers and lords of bop like the guys he mentioned were busy inventing and codifying it right then and there, just as they had been since the dawn of recorded music, and just as they would do right up until the present day.
It's hard to find a "pure" form of music from Fifth Ward. The Nickel has always been more about friction, styles colliding and shattering and emerging as something new. The jazz from the Fifth has always been bluesy and the blues jazzy. Ancient Creole folk was seduced by hard-charging R&B in Fifth Ward's Frenchtown, and zydeco was the result.
The Geto Boys - among the most lyrically profane rappers - have frequently shown a marked gospel influence in both lyrical style and their frequent use of church-y organs. (Sure, most of that influence comes more from South Park's Scarface rather than Fifth Ward's Willie D., but still.) Scratch the surface deep enough and you'll even find country and western underpinnings to a great deal of Fifth Ward music. The one thing virtually all Fifth Ward music has in common is swing.