The Sinterklaas tradition goes back a long time ago. Originally, Sinterklaas' history starts in Turkey. In Myra (Turkey), Saint Nicholas was the bishop. When the bishop died on the 6th of December, in the year 340, his remains were brought to Italy. It might have been that Italy has been mixed up with Spain in the past, because even though Sinterklaas originates from Turkey, the tradition states that Sinterklaas comes from Spain on the day of the arrival in the Netherlands.
St. Nicholas was known as a man with good deeds, which is why he was declared holy. In the Sinterklaas tradition, Pieten throw "pepernoten" and other sweets towards children for them to catch. Historically, this has arisen from the money that St. Nicholas had given to the poor. Where his helpers, the so called Pieten, have come from is not sure. There are all kind of stories about them.