The intersection of West 125th Street and Seventh Avenue in Harlem was, for decades, a center of black nationalism. Street orators — that’s what they were called — climbed onto stepladders and made impassioned calls for African liberation.

When Kwame Brathwaite and his brother Elombe Brath were teenagers in the 1950s, they would walk there from their dad’s dry cleaning shop and listen, entranced, for hours. Mr. Brath once recounted the story of Carlos Cooks, a student of Marcus Garvey, bellowing to a black woman walking by: “Your hair has more intelligence than you. In two weeks, your hair is willing to go back to Africa and you’ll still be jivin’ on the corner.” (Two weeks was just about how long hot-combed styles kept a black woman’s hair straight.)

After a few years of standing rapt at that corner, the brothers helped found the African Jazz Art Society and Studios, an artist collective also known as AJASS. The group produced concerts “to promote awareness of African-derived black music and dance forms,” Tanisha C. Ford, a historian, wrote in her book “Liberated Threads: Black Women, Style, and the Global Politics of Soul.”