Santa Calus - Święty Mikołaj
I don't believe there is a Polish Santa Claus .... only a St Nicholas :o) ...... and I think there is a thread already running discussing this.
As a young boy with Polish parents, growing up in England in the 60's/70's, December 6th was a very special day for my brother and myself as well as all the other children of Polish parents; it was the day St Nicholas came and left presents by your bed, or you went to a local hall where St Nicholas (a parent dressed up) would make an appearance and give out presents to all the Polish boys and girls.
It's a tradition I am continuing with my own two young kids.