Because the Roman empire included parts of Africa, including importing their slaves.
There were black Roman soldiers posted on Hadrian's Wall in the north of England.
There were black Roman soldiers posted on Hadrian's Wall in the north of England.
Traveling large distances was expensive and dangerous and fairly rare outside of a few professions. Soldiers being one of them so to an extent that’s feasible
> including importing their slaves
Why would you import someone from Nubia to Western Europe when you have a relatively ample supply of barbarians being trafficked across the border and there is a significant demand for slaves in Egypt and other provinces nearby.
I mean technically you could run into a Black African somewhere in the Roman Empire but outside of exceptional circumstances that would be almost as likely as winning a lottery