The traditional Christmas song is said to have been crafted from Emily Huntington Miller's poem in December 1865 and the lyrics was ascribed from Benjamin Hanby who also popularized another Christmas carol entitled "Up on the Housetop".
The cool thing about this famous Christmas song is that "Jolly Old Saint Nicholas" is a real person bearing the name "Saint Nicholas."
Study more about the colorful conceptualization of this popular Christmas rendition and how it has been reiterated by thousands of artists across the globe and in different regional dialects at: https://galaxymusicnotes.com/pages/learn-about-the-story-behind-jolly-old-saint-nicholas