It's a well-documented fact that very first snowman was made in Eau Claire, Wisconsin on January 7, 1809 by a Mr. Vernon N. Paul and his nine-year-old daughter, little Yetty Paul. According to Mr. Paul, he told his daughter that the snowman was intended to frighten away the Boxing Day elves. (Popular legend said Boxing Day Elves reclaimed Christmas presents.) Once the Paul family's neighbors saw the snowman, and little Yetty explained to her friends how easy it was to make (and no doubt, how effective it was at keeping the Boxing Day elves away), children all over the town were making snowmen.

Word soon spread and the New York Times dispatched a writer named Hillary Sherpa to check out rumors of a town populated by snow men. Of course, she found that Eau Clairre was not really populated by snow people, but instead, effigies of people, made of snow, "seemed to virtually populate every corner of the town." According to the Ms. Sherpa's article, even though the snowmen and snow women "had an appearance bordering on abysmal, indeed even abominable" the trend caught on and soon spread nationwide by the eve of the Civil War.

When war broke out in South Carolina in 1861, the Times of London (and a host of other international newspapers and news reporting agencies, including Berlin's leading newspaper, Der Kruller) came to the US to report on the war. The Times of London actually was the first international newspaper to pick up a story on the tradition of snowmen, more as a human interest story than anything else. And as they say, "the rest is history."
Source(s):
http://www.nytimes.com/ref/membercenter/…