A whole bunch of big groups from overseas owed a substantial debt to the blues born on these shores. We’re talking Fleetwood Mac (pre-McVie), Animals, Them, Stones, Kinks, Mayall, Yardbirds, Zeppelin, and yes, the Beatles too. Less famous, in most cases, were the progenitors: Big Joe Williams (Baby, Please Don’t Go), Ma Rainey (See See Rider), Junior Wells (You Don’t Love Me), Willie Dixon (I Can’t Quit You Baby), Memphis Slim (Every Day I Have the Blues), Slim Harpo (Shake Your Hips), and Sonny Boy Williamson (Checkin’ On My Baby). Of course, these are amongst the top names in the history of the blues, but if fame for a musician was measured by their bank account, they’d be also-rans to the willing young Brits who “discovered” them. Another good reason to have the blues. Though admittedly, the notoriety of these British Invasion legionnaires playing the music of Black blues artists led to youthful music lovers in places like Racine, Wisconsin, to embrace the genre and a whole new...