When American became embroiled in World War II, it served to increase the exodus of African-Americans from the Southern states northward to cities like St. Louis, Detroit, and Chicago. Former sharecroppers were moving out of the rural areas of Mississippi, Alabama, and Georgia to find jobs in the growing industrial sector and provide better opportunities for their families.
Along with the many agricultural workers who came to Chicago in search of jobs, there were a number of blues musicians that made the trip as well.
Arriving in Chicago, they began mixing with the first generation of immigrants, taking on an urban sophistication in place of their rural roots.
The blues music made by these newcomers took on a new sheen as well, as musicians replaced their acoustic instruments with amplified versions and the basic guitar/harmonica duo of Delta blues and Piedmont blues was expanded into a full band with bass guitar, drums, and sometimes saxophone.
The Chicago blues sounded more full-bodied than its country cousin as well, the music pulling from broader musical possibilities, reaching beyond the standard six-note blues scale to incorporate major scale notes. While the "south side" blues sound was often more raw and raucous, the "west side" Chicago blues sound was characterized by a more fluid, jazz-influenced style of guitar playing and a full-blown horn section.
What we consider to be the "classic" Chicago blues sound today developed during the 1940s and "50s.
Talents like Tampa Red, Big Bill Broonzy, and Memphis Minnie were among the first generation of Chicago blues artists, and they paved the way (and often lent valuable support) for newcomers like Muddy Waters, Howlin" Wolf, Little Walter, and Willie Dixon. During the decade of the 1950s, Chicago blues ruled the R&B charts, and the style has heavily influenced soul, rhythm & blues, and rock music to this day.
Subsequent generations of Chicago blues artists like Buddy Guy, Son Seals, and Lonnie Brooks have incorporated significant influences from rock music,