Here it is the 5th, and we tell children it is the birthday of Sinterklaas.
According to wikipedia he was born on March 15th and died December 6th. But go on telling your children lies until they are ready to hear the truth.
Tbf this was before nation states so the modern borders of Spain didn’t exist yet so why no include modern day Turkey (which existed neither, nor was it populated my the linguistically and culturally ancestors of the modern Turks).