This is about Angela Davis, a black radical who was arrested, but eventually acquitted, of aiding a courtroom escape in 1970 in which four people died. She was the vice-presidential candidate on the US Communist party ticket in 1980.
The lyrics are a parody of black stereotypes. Mick Jagger sang like Buckwheat from The Little Rascals to make his statement of support for Angela Davis. Potentially inflammatory lyrics like "Ten little nigga," did not cause much controversy because it was so clearly a parody.
The working title was "Bent Green Needles."
This was recorded at Stargroves, The Stones' mobile recording studio, during the Sticky Fingers sessions.
Richard Didymus Washington played marimbas on this track. Showing up as "Amyl Nitrate" on the credits, Washington was a percussionist working with Dr. John.
"Piano Man" was inspired by Billy Joel's time playing at a piano bar in Los Angeles. The "real estate novelist" was a guy who always talked about writing a book, but spent all his spare time in the bar.