I'm going on with my research of traditional Christmas stories to make new vintage illustrations hand made in watercolors.
So I discovered that originally Santa's dress was not red, but green.

Of course there are a lot of old tales about Santa Claus.

In north Europe Saint Nicholas was a man dressed in green, that goes to bring gifts to good children. Evil kids were visited by Krampus, a beast-like creature, a hairy demon with horns that went to punish.
In some places on the Alps on december the 5th, there are traditional festivals with people masked like monsters in parades with Saint Nicholas.
When the evening comes, in the dark Saint Nicholas disappears and the Krampus goes to scare children.

In traditional old Catholic icons sometimes Saint Nicholas has a red dress but he was a thin man with an high vertical hat.

The dress with are used to see today is a creation of Coke visualizers. The first Coke advertise with an old fat bearded man in a red dress appears for the first time in 1930, and this is closer to the actual vision of Santa Claus.