"A Visit from St. Nicholas", more commonly known as "The Night Before Christmas" and "'Twas the Night Before Christmas" from its first line, is a poem first published anonymously in 1823 and later attributed to Clement Clarke Moore, who claimed authorship in 1837. Some commentators now believe the poem was written by Henry Livingston Jr..
The poem has been called "arguably the best-known verses ever written by an American" and is largely responsible for some of the conceptions of Santa Claus from the mid-nineteenth century to today. It has had a massive impact on the history of Christmas gift-giving. Before the poem gained wide popularity, American ideas had varied considerably about Saint Nicholas and other Christmastide visitors. "A Visit from St. Nicholas" eventually was set to music and has been recorded by many artists.