The Greeks, Hebrews, Romans, Aztecs, and most African and Native American tribes have practiced slavery at aome time.
It is a pretty safe guess that virtually everyone has a slave somewhere in their ancestry--and an owner.
Oh I know that. My parents were both from Europe -- my mother emigrated in 1929; my father was born here, but his parents came over in the early 1900's. I suppose if you stretch back my ancestry far enough, you will find that someone on either or both sides was a slave of some sort. In fact, if I remember my European history right, those who worked the land were called serfs -- they were for all practical purposes slaves.
I'm just commenting on those who would try to late the guilt for the U.S. slavery period on every white man's shoulder.