Unironically because their ancestors had their share of BGC
At 300bc alexander conquered them, for the next hundred years these places where under minority greek rule in the so called Hellenic period, sort of like spanish latin america
The western parts were latter annexed by Byzantine empire while in the eastern parts collapsed
Alexander himself had 3 wifes from the area while every man in his army was encouraged to marry a local woman as well
In the western parts which were under byzantine controll untill around 1300AD many of these genes survive untill today
Vid related is in egypt, a yearly festival of egyptians with greek ancestry
https://www.youtube.com/watch?v=31A66Pqg9f0 
