“…..Washington Irving’s St. Nicholas strongly influenced the poem’s portrayal of a round, pipe-smoking, elf-like St. Nicholas. The poem (The Night Before Christmas) generally has been attributed to Clement Clark Moore, a professor of biblical languages at New York’s Episcopal General Theological Seminary. However, a case has been made by Don Foster in Author Unknown, that Henry Livingston actually penned it in 1807 or 1808. Livingston was a farmer/patriot who wrote humorous verse for children. In any case, “A Visit from St. Nicholas” became a defining American holiday classic. No matter who wrote it, the poem has had enormous influence on the Americanization of St. Nicholas.
Other artists and writers continued the change to an elf-like St. Nicholas, “Sancte Claus,” or “Santa Claus,” unlike the stately European bishop. In 1863, political cartoonist Thomas Nast began a series of annual black-and-white drawings in Harper’s Weekly, based on the descriptions found in the poem and Washington Irving’s work. These drawings established a rotund Santa with flowing beard, fur garments, and an omnipresent clay pipe. As Nast drew Santas until 1886, his work had considerable influence in forming the American Santa Claus. Along with appearance changes, the saint’s name shifted to Santa Claus—a natural phonetic alteration from the German Sankt Niklaus and Dutch Sinterklaas.
Santa was then portrayed by dozens of artists in a wide variety of styles, sizes, and colors. However by the end of the 1920s, a standard American Santa—life-sized in a red, fur-trimmed suit—had emerged from the work of N. C. Wyeth, Norman Rockwell and other popular illustrators. In 1931 Haddon Sundblom began thirty-five years of Coca-Cola Santa advertisements that popularized and firmly established this Santa as an icon of contemporary commercial culture.
This Santa was life-sized, jolly, and wore the now familiar red suit. He appeared in magazines, on billboards, and shop counters, encouraging Americans to see Coke as the solution to “a thirst for all seasons.” By the 1950s Santa was turning up everywhere as a benign source of beneficence, endorsing an amazing range of consumer products. This commercial success led to the North American Santa Claus being exported around the world where he threatens to overcome the European St. Nicholas, who has retained his identity as a Christian bishop and saint.” From “Saint Nicholas and the Origin of Santa Claus” at the “St. Nicholas Center” website which is full of interesting information concerning St. Nicholas of Myra.