Most of the great Blues singers come from the Mississippi delta from the upper area of Mississippi state to Memphis Tennessee. Son House, Robert Johnson and BB King all come from this area. In fact, in Clarksdale Mississippi, there is a Delta Blues Hall of Fame.
This area was a big area for cotton farming, and no doubt, saw many a blues singer producing the Blues while enslaved. Even after slavery ended during the mid Civil War, freed slaves became sharecroppers who fared a little better.
Sharecroppers rented land and equipment from former slave owners and spent the whole planting season planting cotton and other cash crops unde the tutelage of the wealthy landowners. The rent was high for both the land and tools to produce the finished cotton product. The sharecropper had no choice since he had no other choice since being freed from human bondage. He simply had to labor the only way he knew how, using the only methods he could muster. Rented land and rented tools.
For historians, the explanation for the misery is simple. Free, or inexpensive, labor. For the victimized, it too was an easy explanation. Greed. For music lovers, it was the Blues. Oh, the Blues...