The website History Debunked has an insightful and thought-provoking video about the modern assertion that there were sub-Saharan Africans living in Roman Britain. This assertion is based on the interpretation of a very few archaeological discoveries. The video, which challenges this interpretation, can be seen at Black people in Roman Britain; the collapse of a modern fairy story
That is not to say that there were never, ever, black Africans in Britannia in almost four centuries of Roman rule. What it does say is than the modern anxiety to find such a presence ignores the real evidence of archaeology and anthropology. Not only does it ignore the detailed evidence but latches on to something to prove or promote a contemporary argument, not an historical fact.
Furthermore I will add that I have known archaeologists who rush to announce a spectacular discovery on an overly hasty identification, only to have to retract it - in one case quite literally the next day.