Black Peter (Zwart Piet), while now a benevolent companion of Sinter Klaas, was at one time a more sinister character. During the Middle Ages, he threatened to punish the children if they were naughty by throwing them into his sack or giving them switches (coal also?) instead of presents. Today, however, he helps Sinter Klaas distribute gifts, even offering to go down chimneys to fill the children’s shoes, thereby saving the holy Bishop from getting dirty. Black Peter, often depicted as a boy or young man, wears a Moorish costume, probably because Spain ruled over Holland during the 16th century. So Zwart Piet is a Moor. How interesting to have a black character in Dutch and Belgian Christmas folklore.
Read more here.