What famous saint who is associated with Christmas whose feast day is celebrated during Advent?

St. Nicholas of Myra, who has a feast day on December 6, is often associated with Christmas as "Santa Claus." This is strictly a fable and commercial fabrication to increase sales at Christmas. Nicholas has no relevancy at all to the Christmas Holiday. St. Nicholas was a wonderful and generous bishop and patron saint of children who does not deserve this desecration.