Reggae
Romans enslaved people from the entire Roman Empire and not just for war, even physicians and accountants were often slaves. You’re quoting one country, which due to the timeline had a vastly smaller population than in 16th-19th century and comparing it to the enslavement of an entire very large continent during more recent times.
The Romans weren’t the only ones to enslave. The Greeks did it. Slavs from Eastern Europe were imprisoned by Spanish Muslims in the 9th century. We had serfdoms in Europe, which existed in places like Austria until almost the end of 18th century and Russia in 1860. No serfs weren’t chattel to be bought and sold. Instead they had to tend the land, weren’t allowed to leave without permission, couldn’t own the land and worked to eat. If the land was sold, the serfs were transferred en masse to serve the next land owner. Entire countries lived this feudal system from around 11th century, in fact, I think a lot of the European continent did. The last serfs in Britain were in 1574 so that’s 500 years of forced enslavement. The Romans also had such a system for a while. Serfdom in Britain was pretty much then replaced with indentured servitude after the peasants revolt so also grim but at least people could earn themselves free.
All slavery is atrocious. Black people are still feeling it because enslavery of their people ended such a disgustingly short time ago. Of course as a nation we should bloody well remember what happened and feel shame for what our ancestors did to our fellow humans for profit. And none of what I have said above is trying to excuse or say the abduction, murder and enslavement of millions of black people wasn’t anything other than barbaric.
In 400 years time, we will probably all be mixed raced - as we are already, it’s just such ancient history - and people then will hopefully look back at slavery as something very much in the past. However, for that to happen, the approximate 40.3 million slaves of one kind or another around the world will have to be set free.
All of that said, of course, I do not understand your anger. I understand my anger as Caucasian woman. But not yours.