Haven't seen this film Billy, I'll check it out.
I've just googled it and I noticed that Irene Papas (superb actress, she's an icon here) also co-starring. She played with A.Quinn also in "Guns of Navarone" and in "Zorba", of course.
https://en.wikipedia.org/wiki/Irene_Papas
Harry Mark Petrakis was an American novelist and writer of short stories. He was best known for depicting the life of Greek-American immigrants in the Greektown neighborhood of Chicago, Illinois.
Anthony Quinn played the lead in this movie. He was cast again as a Greek character in the Harry Mark Petrakis novel A Dream of Kings. Quinn was chosen for the part after having played Zorba the Greek. The background for the film was Chicago.
A DREAM OF KINGS 11 minute trailer. https://www.youtube.com/watch?v=fpb92z91aBM