What is Billie Holiday's significance in the autobiography?

Billie Holiday's significance in the autobiography, like that of other figures, such as Dinah Washington and Redd Foxx, is peripheral yet helpful in understanding the cultural atmosphere in which Malcolm Little came of age, then became transformed into Malcolm X.

He first mentions Holiday when talking about The Braddock Hotel on 126th Street, "near the Apollo's backstage entrance." A lot of celebrities hung around in there, including "Dizzy Gillespie, Billy Eckstine, Billie Holiday, Ella Fitzgerald, and Dinah Washington" (83).

Later, shortly before leaving for Boston, he is working as a numbers-runner for a man who goes by the name of "West Indian Archie." He is heading to the Onyx Club with Jean Parks, a restaurant owner, to see Holiday perform. At this time, Billie Holiday was at the apex of her fame:

'Billie Holiday' and those big photo blow-ups of her were under the lights outside. Inside the tables were jammed against the wall.

Because Holiday knew Malcolm Little at the time, as well as Jean Parks, she went over to say 'hello' and, though Malcolm was high, knew him well enough to discern something else was wrong (he was worried that "West Indian Archie" would avenge him for getting a number wrong). 

Malcolm, Jean Parks, and Holiday take a picture together. That, he notes, was "the last time [he] ever saw Lady Day" (141):

She's dead; dope and heartbreak stopped that heart as big as a barn and that sound and style that no one successfully copies. Lady Day sang with the soul of Negroes from the centuries of sorrow and oppression. What a shame that proud, fine, black woman never lived where the true greatness of the black race was appreciated! (141)

It is well-known that Billie Holiday was a heroin addict. She died in 1959. There was a weariness and heart-brokenness in her voice that, as Malcolm explains, could have acted as a metaphor for the spirits of black people at various low phases of American life. She is appreciated now, but was not given much appreciation in her time. While lauded as a performer, she was treated as shabbily as other black people who attempted to enter luxury establishments at this time: she was either rebuffed or forced to enter through the kitchen. Her greatness could never be fully realized in her lifetime because white America was unable to look past her skin.