The Belsnickel is a Santa type character who is popular mostly in Germanic cultures. He is also popular amongst the Pennsylvania Dutch. Dwight Schrute made an appearance as Belsnickel in an episode of The Office, which likely brought the character some fame. He is heavily related to another German character known as Knecht Ruprecht.
Belsnickel is like an extreme Santa. While he does bring gifts to the good children, he is also an intimidating figure, as well as a disciplinarian. He is adorned with fur and a long tongue. Sometimes he wears a mask, but he always is seen carrying a switch to beat the bad children with. He does have some association with Krampus, but the two are not known to travel together.
The region he was most known in is called Palatinate. Many people from that area immigrated to Pennsylvania and Indiana. As a result, the traditions and beliefs around the Belsnickel traveled with them. Tales of the character spread throughout the regions and his name became synonymous with making children behave a little bit quicker.