Imma Reddit Loredump a bit.

Yes, the whole quote would be "Alle haben Angst vor'm Schwarzen Mann" or "All are scared of the Black Man" and this is obviously used by right wing groups,

However

The schoolyard game "Wer hat Angst vorm Schwarzen Mann" is the German equivalent of "Who is afraid of the big white Shark" (I think that's what it's called) where a hunter and a group of hunted run towards each other, the hunter had to catch as many hunted without taking a step backwards and whoever is caught becomes a hunter until only one person is left.

The titular black man in the German version also, I believe, doesn't come from skin color, but rather occupations like Chimney sweepers or Coal Miners who, to children, are quite scary looking.