The song is about the entrapments of coming of age and the problems that come associated with it.
In an interview in The Tech, 12 April 1988, O'Connor said:

“Mandinkas are an African tribe. They’re mentioned in a book called Roots by Alex Haley, which is what the song is about. In order to understand it you must read the book.”

In her memoir, Rememberings, O'Connor shares that:

Mandinka' was inspired by the television series “Roots”, based on Alex Haley’s novel about slavery. I was a young girl when I saw it, and it moved something so deeply in me… I came to emotionally identify with the civil rights movement and slavery, especially given the theocracy I lived in and the oppression in my own home.

In the song, O’Connor sings “I don’t know no shame, I feel no pain/I can’t see the flame” to let the listeners know her main point behind the song. She later sings in the song “I have refused to take part” which can be interpreted into how she refused to take part in the music industries sexist practices.