Where was the black population of Europe concentrated since the time of the Roman Republic?

Explanation:

Demographically, the Roman Empire was a typical premodern state. It had high infant mortality,  After population decline following the disintegration of the western half of the Roman state in the fifth and sixth The late period of the Roman Republic provides a small exception to this general rule: serial statistics for Roman.

independent innovation during the abbasid caliphate

if you're talking about (ww2) they went bankrupt and their currency was worth nothing

explanation: