We typically don’t think of Africans in London in the 1500s, but they were there, as proven in parish and other records. Thankfully, they were rare enough that when there was a record pertaining to them, their ethnicity is recorded. But by 1600, after the Queen’s legendary decades-long conflict with Spain where galley slaves from Spanish ships were “rescued” when the ships were captured, the number of Africans and other “Moorish” people were becoming problematic, at least to the Queen, and she sought to repatriate at least some of them to “Barbary.”
Recently, the BBC ran a wonderful story about this which you can find at this link: http://www.bbc.co.uk/news/magazine-18903391
In the haplogroup E1b1a project, it’s not uncommon for a person who knows their family to be “white” to discover their haplogroup is of African origin. Many times, one can account for this by more fully researching the early colonial records of America, but not always. Perhaps we need to extend the research net a bid wider to include both London and Bristol records.