Some history:
"Johnny Otis[1] (born Ioannis Alexandres Veliotes, December 28, 1921 – January 17, 2012) was an American singer, musician, composer, arranger, bandleader, talent scout, disc jockey, record producer, television show host, artist, author, journalist, minister, and impresario.[2] A seminal influence on American R&B and rock and roll, Otis discovered artists such as Little Esther, Big Mama Thornton, Jackie Wilson, Little Willie John and Hank Ballard and Etta James. Known as the original "King of Rock & Roll",[1] he is commonly referred to as the "Godfather of Rhythm and Blues".[3]
Otis was born to Greek immigrants Alexander J. Veliotes, a Mare Island longshoreman and grocery store owner, and his wife, the former Irene Kiskakes, a painter.[1][4] He had a younger sister, Dorothy, and a younger brother, Nicholas A. Veliotes, former U.S. Ambassador to both Jordan (1978–1981) and Egypt (1984–1986)). He grew up in a predominantly black neighborhood in Berkeley, California, where his father owned a neighborhood grocery store. Otis became well known for his choice to live his professional and personal life as a member of the African-American community.[5][6][7] He wrote, "As a kid I decided that if our society dictated that one had to be black or white, I would be black."[8]..."
https://en.wikipedia.org/wiki/Johnny_Otis
"Milton Mesirow, better known as Mezz Mezzrow (November 9, 1899 – August 5, 1972) was an American jazz clarinetist and saxophonist from Chicago, Illinois.[1] Mezzrow is well known for organizing and financing historic recording sessions with Tommy Ladnier and Sidney Bechet. Mezzrow also recorded a number of times with Bechet and briefly acted as manager for Louis Armstrong. He is equally well remembered, however, for being a colorful character, as clearly portrayed in his autobiography Really the Blues, as for his music....Mezzrow praised and admired the African-American style. In his autobiography Really the Blues, Mezzrow writes that from the moment he heard jazz he "was going to be a Negro musician, hipping [teaching] the world about the blues the way only Negroes can."
Mezzrow married a black woman, Mae (also known as Johnnie Mae), moved to Harlem, New York, and declared himself a "voluntary Negro." In 1940 he was caught by the police to be in possession of sixty joints trying to enter a jazz club at the 1939 New York World's Fair, with intent to distribute. When he was sent to jail, he insisted to the guards that he was black and was transferred to the segregated prison's black section....."
https://en.wikipedia.org/wiki/Mezz_Mezzrow