I don't understand racism. Although it depends on the idea of the superiority of a particular genetic inheritance, in practice that is meaningless and anyone in the UK will have a pretty mixed inheritance.
The freed slaves in the UK disapppeared without trace into the general population. Waves of immigration to these islands over the centuries have brought in people from across Europe and beyond. There is evidence for example of trading links between South West England and the Middle East. It seems inconceivable that those traders didn't leave a baby or two behind. Similarly, the track of the Armada around the north of Scotland and Ireland led to many shipwrecked Spaniards who then lived out their life in the communities in which they were washed up, bringing with them their own mix of Southern Europe and North African genes.
A google search on my surname shows it spread across Northern Europe - especially Germany, Netherlands and Denmark. I found at least one Rabbi. I know that I have at least one Catholic priest as a distant cousin and other relatives who were nonconformists of various types.
Anyone born in the UK and Europe - and that means in North America, Australia, New Zealand too will have a very wide genetic and religious background.
Racism is a denial of your heritage, not an affirmation.