Fear of black people
I am of european ancestry if you haven't guessed already, and I was born with a fear of black people. For some reason I was particularly afraid of black people wearing white people's clothes, especially old fashioned European clothes.
There really weren't many darkly coloured people where I lived and I barely ever saw one in real life, so I don't think a black person would ever have harmed me at all, and it's not as if I hate them or anything.
As a child someone gave me a toy golliwog and I was so afraid of it that my mum had to put it away somewhere I would never see it.
I have pretty much grown out of it now, but now and then it still catches me off guard.