" Black Power was a political movement that arose in the middle 1960s, that strove to express a new racial consciousness among Blacks in the United States. Robert Williams, who revived the Monroe, NC chapter of the NAACP and later entered exile in Cuba and China, was the first to put the actual term to effective use in the late 1950s. Williams, who was also the first to publish the poetry of Ray Durem, used the phrase "Black Power" in the American political context."

http://www.umich.edu/~eng499/concepts/power.html)