In the early 1900s, a sound came out of African-American communities in the southern U.S. states that came to be called the blues. Some of the deepest roots of the music come from the rich farming region known as the Mississippi Delta.
A little over a century ago, poor African-American laborers in Mississippi took up European instruments like the guitar and harmonica to play soulful and expressive music called the blues.
It was a time when the rich fields of the Delta region required many laborers.
Clarksdale, Mississippi, home of the Delta Blues Museum
, was a transportation hub then, according to museum director Shelley Ritter.
"With so many farms, there was an opportunity for a lot of work and then we had the river here and the railroad was here," she said.
One of the largest exhibits in the museum is the reassembled farm cabin where famed bluesman Muddy Waters once lived. He and other bluesmen honed their skills in Clarksdale, which offered workers music and more.
"On Saturdays or on weekends, when the laborers were given time off, they would all come into town and avail themselves of all the vices, if you will, as well as the wares," Ritter said.
Ritter says aspiring bluesmen who couldn't afford a guitar sometimes played on a "diddly bow," a wire strung between two nails.
The sound it produced may have influenced the guitar style now associated with Delta blues.
Musicologist David Evans, who teaches at the University of Memphis, has spent a lifetime playing the blues and studying its characteristics.
"The blue notes and blues scale, these bent notes and neutral pitches, sliding pitches, however you want to characterize them and there are various ways to express them vocally and instrumentally," he said.
Evans says the blues borrowed elements from Europe as well as Africa, but its inventors were thoroughly African-American.
"It was a new synthesis, but it was pretty clear that that synthesis was accomplished by black musicians," he said.
While the Delta region, as well as Memphis and New Orleans, all have a claim on the blues, Evans says there is evidence it developed over a wide region.
"The earliest reports come from all over: Mississippi, Georgia, Texas, cities like St. Louis," he said.
The disapproval of community leaders, black and white, and preachers who called it "devil music," only enhanced its allure, says Evans.
"That made the blues variously exotic, exciting, dangerous," he said.
And that may be part of what keeps the blues alive today.
It may have started in the American South, but the blues now belongs to the world.