Al Jolson had a tremendous relationship with the black community. He championed their cause and was credited with fighting against discrimination against African Americans on Broadway as early as 1911.
From Wiki: While growing up, Jolson had many black friends, including Bill "Bojangles" Robinson, who became a prominent tap dancer. As early as 1911, at the age of 25, Jolson was noted for fighting discrimination on Broadway and later in his movies. He promoted a play by Garland Anderson which became the first production with an all-black cast produced on Broadway. He brought a black dance team from San Francisco that he tried to put in a Broadway show.; He demanded equal treatment for Cab Calloway, with whom he performed duets in the movie The Singing Kid.
Jolson read in the newspaper that songwriters Eubie Blake and Noble Sissle, neither of whom he had ever heard of, were refused service at a Connecticut restaurant because of their race. He tracked them down and took them out to dinner, "insisting he'd punch anyone in the nose who tried to kick us out!"According to biographer Al Rose, Jolson and Blake became friends and went to boxing matches together.
Film historian Charles Musser notes, "African Americans' embrace of Jolson was not a spontaneous reaction to his appearance in talking pictures. In an era when African Americans did not have to go looking for enemies, Jolson was perceived a friend."According to music historians Bruce Crowther and Mike Pinfold: "During his time he was the best known and most popular all-around entertainer America (and probably the world) has ever known, captivating audiences in the theatre and becoming an attraction on records, radio, and in films. He opened the ears of white audiences to the existence of musical forms alien to their previous understanding and experience... and helped prepare the way for others who would bring a more realistic and sympathetic touch to black musical traditions." Black songwriter Noble Sissle, in the 1930s, said "[h]e was always the champion of the Negro songwriter and performer, and was first to put Negroes in his shows". Of Jolson's "Mammy" songs, he adds, "with real tears streaming down his blackened face, he immortalized the Negro motherhood of America as no individual could."