Culliford, for some reason, could not remember how to say "sel" ("salt"). He was not having a stroke nor was he suffering from some sort other sort of significant neurological disorder, temporary or otherwise. Colloquially speaking, Culliford had a brainfart, and uttered a seemingly nonsense sentence: "passe-moi [pause, as he searched in vain for the right word] le schtroumpf." His dinner mate, Franquin, took the opportunity to mock Culliford, and replied -- as translated into English -- "Here's the Schtroumpf — when you are done schtroumpfing, schtroumpf it back." The two, on vacation together, shared a laugh and found a new game; for the rest of the weekend, they continued substituting "schtroumpf" and derivations thereof for various words.
In most cases, this would be the end of the story. But Culliford's profession allowed him to use " schtroumpf" in a new, fabulous way. Culliford was a cartoonist better known by his pen name, Peyo. He was the author and illustrator of a comic, the story of Johan, a medieval page to the king, and his faithful sidekick, Peewit. Johan and Peewit (its subsequent English title) was regularly published in a French children's comic magazine. In October of 1958, Peyo introduced new characters to Johan's world -- tiny blue things called " schtroumpf" which, like Peyo and Franquin had earlier that year -- substituted the word " schtroumpf" at seemingly every opportunity.
It took a few decades, but by 1981, Le Schtroumpfs reached the United States, but under their Dutch name: the Smurfs.
Link | Image: Peyo