OMG!!! How do you sustain charges of “modern racism today”? You write fiction as history.
Yes, there are have been “blacks” in Britain from further back than the modern era. But “blacks” were not in the populations of Britain at the time of stonehenge or earlier.
The earliest “blacks” in the British Isles came with the Roman legions. Not that much is known or written about how many stayed in the Bristish Isles and became part of the local population.
Much later on from the 11th century and before the formalized European “slave trade”, there are different reports of “blacks” among the British population. If they were truly “black” as opposed to merely being from Africa, particulary north Africa from Egypt to Morrocco (which was never predominately “black” is uncertain. The terms “Moor”, “Saracen”, “Blackamoor” (a “dark skiined person not from Europe), seemed to have been labels thrown around about people who came from al parts of North African.
What the modern world has done in a great disservice to history is conflated the descriptor “African” to mean “black” which is an error both historically and at present.
"BLACKAMOOR" was often used, way back when ( in the British Isles ), to refer to peoples from the Levant ( Middle East ) and NEVER to Negros!
When Shakespeare wrote OTHELLO, the lead in that play was NOT an African Negro,but a Middle Easterner.
Ancient Roman writers and a bit more modern ones, who called Cleopatra "dusky", were saying that her skin type was not as as pale as Scandinavians, Gauls ( the early French an early Germanic tribes ), or Brits.
Hakeem Jeffries' uncle, Leonard Jeffries, was the crazy prof who got the whole, VERY racist, garbage about how Cleopatra and everyone who ever did anything great were "black" and that the whites "STOLE" the knowledge and inventions from black Africans, back in the early 1970s. By the early 1990s, he and his works were discredited, laughed at, sued, and fired from CCNY.
And Cheedar Man may have had darker skin than what we think of re Caucasians, he had blue eyes and didn't look Negroid at all!