Briefly, Cleopatra descended from the inbred European (Macedonian) Ptolemaic line. But we don't have unambiguous evidence for the genetic background of her mother or her grandmother. Cleopatra may have been nearly entirely Macedonian (with a little Persian). Or she may have been as much as 75% Egyptian. We don't know.
Any cinematic interpretation that keeps within those parameters is credible.
I look forward to seeing Ms. Gadot as Cleopatra. I also hope others produce a movie that interprets Cleopatra as mostly African. We should explore all the possible pasts that history hands us.
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