During America’s mid-20th century Great Migration, black Southern blues singers made their way north, part of the industrial and cultural boom. Chicago’s urban environment changed the blues forever, as former Mississippians like Muddy Waters and Howlin’ Wolf harnessed the visceral jolt of electric guitars and drums to amp up the wail and roar they had already developed down south. In the Windy City, the primal stomp of the Delta was not only amplified but intensified, pumping up the artists’ emotional outpouring into something more physically impactful than any other brand of blues. With crowds turning out for loud, scrappy drinking music, and the legendary Chess label spreading the sound to radio and record stores, Chicago blues’ originators took perennial themes like love, longing, despair and exultation, investing them with a momentum that would soon pave the way for rock 'n' roll.