"A Visit from St. Nicholas", also 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 generally attributed to Clement Clarke Moore

Clement Clarke Moore

Clement Clarke Moore was an American professor of Oriental and Greek literature at Columbia College, now Columbia University. He donated land from his family estate for the foundation of the General Theological Seminary, where he was a professor of Biblical learning and compiled a two-volume...

, although the claim has also been made that it was written by Henry Livingston, Jr.

Henry Livingston, Jr.

Henry Livingston, Jr. may have written the poem known as "A Visit from St. Nicholas", although more popularly as "The Night Before Christmas", which is generally attributed to Clement Clarke Moore....

The poem, which has been called "arguably the best-known verses ever written by an American", is largely responsible for the conception of Santa Claus

Santa Claus

Santa Claus is a folklore figure in various cultures who distributes gifts to children, normally on Christmas Eve. Each name is a variation of Saint Nicholas, but refers to Santa Claus...

 from the mid-nineteenth century to today, including his physical appearance, the night of his visit, his mode of transportation, the number and names of his reindeer, as well as the tradition that he brings toys to children.