LOL....apparently, it is a slur that was used by European settlers (AKA pieds-noirs, as the French called them) in the former French colonies of Tunisia and Algeria.
Actually, pied-noir is a slur itself, like "trailer trash" or "white trash".
Interesting...I did not know that. So, the French in the mainland used a slur for fellow Frenchmen in North Africa. Very interesting...I wonder if they had similar slurs/terms for the French in Asia. Any idea?