The way he puts it:
Many Negroes will not find themselves in what follows. This is equally true of many whites. But the fact that I feel a foreigner in the worlds of the schizophrenic or the sexual cripple in no way diminishes their reality. The attitudes that I propose to describe are real. I have encountered them innumerable times.
His other main work, Wretched of the Earth also deals with some of the same questions, except in the context of a national resistance movement against colonial oppression (the Algerian Revolution).
Some Quotes from Black Skin, White Masks
Some excerpts from Wretched of the Earth and related literature