Coca-Cola popularized the modern image of Santa Claus as a jolly, plump man in a red suit through its holiday advertising campaigns.

In the 1930s, the company hired artist Haddon Sundblom to create a series of holiday-themed advertisements featuring Santa Claus enjoying a Coke. Sundblom's Santa was based on Clement Clarke Moore's 1823 poem "A Visit from St. Nicholas" (commonly known as "The Night Before Christmas"), which described Santa as a "jolly old elf."

Sundblom's Santa quickly became popular and was featured in Coca-Cola's holiday advertisements for decades. The image of Santa Claus as a happy, rotund man in a red suit became widely recognized and eventually became the standard portrayal of Santa in popular culture.

In addition to its advertising campaigns, Coca-Cola has also played a role in promoting the idea of gift-giving and celebration during the holiday season. The company has sponsored holiday events and charitable causes, helping to further embed the idea of Christmas as a time of joy and giving in popular culture.