If you ask someone to picture Father Christmas, people from many Western cultures will have an image of a jolly, rotund man in a red suit with a white beard.

In Sweden, this image is often combined with the folktale figure of the tomte, a small gnome resembling an old man that was thought to guard each farm and home.

But the image of Santa Claus in a red suit actually only dates back to the 1930s, and it’s almost entirely down to drink manufacturers Coca Cola — and an illustrator born to Nordic immigrants. In 1931, the drinks giant commissioned images of Santa Claus to be used in their advertising, as part of their effort to make Coca Cola synonymous with the festive season, rather than just a cool drink for summery days.

The man they chose for the job was Haddon Sundblom, who was born in Michigan to a Swedish-speaking family. His mother came from Sweden while his father was from the Finnish, Swedish-speaking, Åland Islands.

Sundblom took inspiration from the 1822 poem A Visit From St. Nicholas (“‘Twas the Night Before Christmas”) by Clement Clark Moore when creating the image, which was used in the first Coca Cola Christmas adverts.

He was commissioned to paint more versions for later years, including ads in the late 1930s showing families leaving out Coke for Father Christmas, which inspired some people to follow suit.

According to Coca Cola, “People loved the Coca-Cola Santa images and paid such close attention to them that when anything changed, they sent letters to The Coca-Cola Company. One year, Santa’s large belt was backwards (perhaps because Sundblom was painting via a mirror). Another year, Santa Claus appeared without a wedding ring, causing fans to write asking what happened to Mrs. Claus.”

Sundblom painted the Coca Cola Santa until the mid 1960s, but even today the company’s Christmas ads are based on the Swedish-American’s original artwork.

For people in countries like the UK, Coca Cola’s festive adverts featuring their branded truck are a sign that the holiday season is approaching. But in Sweden, the ancestral home of the Coca Cola Santa’s creator, it’s a different soft drink that dominates the holidays: julmust.