Over time, Saint Nicholas' legend spread far and wide, and he became a sort of superhero of the medieval world. People believed he could perform miracles, and his feast day, December 6th (or 5th in some countries), became a time for gift-giving and celebration. In many countries, children would leave out shoes or stockings on the eve of his feast day, hoping to wake up to find them filled with treats and small toys.
In the Netherlands, Saint Nicholas is known as Sinterklaas, and his arrival is a major event, with parades and parties galore. He's said to ride a white horse and bring gifts to children with the help of his trusty helpers, the Zwarte Pieten (Black Peters). It's a fun and festive time, with lots of sweets and spiced treats to enjoy.