Black Peter or Zwarte Piet is a demonic dwarf from the folklore of Belgium and the Netherlands. He appears each Christmas as the evil helper of Santa Claus (or Sinterklaas) to punish children for their bad behavior.
Sinterklaas is the Dutch and Belgian version of Santa Claus. He is also known as Sint Niklaas (Saint Nicholas). According to legend, he triumphed over a devilish dwarf called Zwarte Piet (Black Peter) and made him his slave.
Black Peter lives in a coal mine in Spain. His skin is black because of the soot and coal dust from the mine. His hair is singed by the fire from all the chimneys he has to climb down.
He spends the year spying on the children of Belgium and Holland, taking note of who has been good and who has been wicked. On Christmas eve, he sets out from his coal mine, squeezing himself through the narrow tunnels and riding off on his coal-cart which is pulled by plague-ridden, undead rams.
Every Christmas, Black Peter is forced to accompany Santa Claus as he goes from house to house, distributing his presents. While Santa rewards the good children, Black Peter takes delight in punishing the bad ones. Children who misbehave do not receive any presents from Santa. Instead, Black Peter will leave a bundle of twigs or a lump of coal in their Christmas stocking as a warning.
If the children have been really bad, or have not heeded his warning, Black Peter will snatch them from their beds and throw them into his sack, which is full of hungry rats. He kidnaps the boys and girls and takes them back to his coal mine where chains them up and makes them his slaves. The poor children are forced to dig coal forever while Black Peter amuses himself by poking them with sharp pins. If they ever grow too sick or tired to work, Black Peter will eat them.