In the latter half of the 18th century England had a Black population of around 15,000 people. They lived mostly in major port cities – London, Liverpool and Bristol – but also in market towns and villages across the country. The majority worked in domestic service, both paid and unpaid.

Whilst slavery had no legal basis in England, the law was often misinterpreted. Black people previously enslaved in the colonies overseas and then brought to England by their owners, were often still treated as slaves. Some individuals who had formerly been enslaved got baptized, believing this would ensure their freedom. Others took advantage of being on English soil and absconded. Notices for ‘runaway slaves’ featured in newspapers during this period.

kilde:

https://historicengland.org.uk/research/inclusive-heritage/the-slave-trade-and-abolition/sites-of-memory/black-lives-in-england/