Simplify the following text for a Grade 11 native English-speaking person.
Original: Sinterklaas is a traditional Winter holiday figure in Dutch-speaking Europe ( Netherlands and Flanders ; today also known in territories of the former Dutch Empire , including South Africa , Aruba , Suriname , CuraÃ ao , Bonaire , and Indonesia ) ; he is celebrated annually on Saint Nicholas ' eve ( 5 December ) or , in Belgium , on the morning of 6 December .
Simplified: Sinterklaas ( also called Sint Nicolaas ) is a traditional winter holiday figure in the Netherlands , Aruba , Suriname , Netherlands Antilles and Belgium . Every year he is celebrated in The Netherlands , one day before Saint Nicholas died ( 5 December ) and on ( 6 December ) in Belgium .