What's a Christmas celebration without a little blackface? In the Netherlands and Belgium, Saint Nicholas (known as Sinterklaas) arrives on a boat from Spain with multiple Zwarte Pieten in tow. Zwarte Piet, of course, means "Black Peter," and the characters are portrayed by people in blackface.
For a while, these characters were said to be Sinterklaas' slaves, and then the story changed to state that Black Peter was a slave that Sinterklaas had set free. Recently, the whole "slave trade" angle is pretty much gone, and their black faces are explained away by chimney soot.
You may be shocked to learn that this tradition has come under scrutiny in recent years due to its racist nature. Who could've seen that coming?