This is a good explanation of Dogan Dursum on facebook he asked , let the world know ..! , and therefore I like to translate it into English, especially for those who do not understand Dutch traditional feast. and in so doing interfered.

The history of Saint Nicholas. 

St. Nicholas fled to Spain later in life.
Originally, Saint Nicholas was a bishop of Turkish origin and nationality off a Turkish port town which was very important at that time.
Here he became internationally famous.
Because he , very unorthodox in that time, liberated ( black African ) child slaves
from the slave ships entering the port,  and took them as a servant in the service . The paid job, " Knight " , gave this child slaves independent autonomous status.

Therefore  St. Nicholas  goes as a friend of children through life . His black servants are originally intended as a symbol against slavery and oppression.
A better symbol against racism than "Sinterklaas"  ( and his black servants ) is not really there. "
Maybe if more people would know that, the discussion stops at last and we can just enjoy all together this wonderful tradition .

Dogan Dursun 
Let the world know 
Can you please share

Original Dogan Dursun - translation by Josh.

I hope that people understand in the Netherlands this Black Knight is one of the most admirable people we know. He is friendly and not a slave, a relief of St Nicholas by free will.