Welcome, Turk! Hope to see many more thoughtful posts from you!
In general, there's never a shortage of prejudice, unfortunately, against people who don't speak, look like, worship, etc., like the majority. But in the case of GF, Virgil Sollozzo, a Sicilian, was called "The Turk" because he had poppy fields in Turkey that produced the opium base for his heroin trade, and because he had a Turkish wife.