Meet zwartepiet and sinterklaas:
They are part of a children's tradition in Belgium and Holland for a couple of centuries now, where in the first week of December the tradition states that Sinterklaas (the saint figure), and his zwartepiets (helpers) arrive to our countries by steamboat from Spain, to deliver presents to all children on the night of the 5th to 6th of December.
Sinterklaas rides a white horse, and it's the job of the zwartepiets to crawl through the chimney and deliver the presents to the kids that have been good in the past year. Hence they are black because of crawling through all those chimneys.
But in recent years black people suddenly started to get offended and called zwartepiet racist. It escalated where there were a lot of protests disrupting the public appearances of Sinterklaas and zwartepiet to the children. It even became violent...
Now, thanks to political correctness, after hundreds of years zwartepiet's appearance has been altered to satisfy the camp that finds it to be racist.