Three things happened to the people that ruled Europe.
For starters, those that were there either fought and encountered genocide or fought, survived, and fled.
For those that took refuge, in the inner sanctum of Europe are still there just like all other black people who are in countries outside of Africa but you never catch a photograph, a tv interview, or any media glimpse of them.
Marginalized as usual.
By the way, this was thousands of years BEFORE the Moors, just so we are clear.