I am dark skinned (proudly) and I was surprised to see Saudi Arabians darker than me when I was there. I knew they were descended from slaves. What I came to learn later was that they were treated like shyt a lot and when there is some sort of argument, traffic accident, whatever, the Arabs will call them the arabic word for slave. There are also black Emeratis (UAE, Oman, et) all of the middle east as well.