Irving layers several styles on top of one another to play with truth, history, and storytelling. The main story (narrated by Diedrich Knickerbocker) is conversational, almost as though Knickerbocker is telling a story to friends or neighbors:
In that same village, and in one of these very houses (which, to tell the precise truth, was sadly time-worn and weather-beaten), there lived many years since, while the country was yet a province of Great Britain, a simple, good-natured fellow of the name of Rip Van Winkle.
Knickerbocker is a scholar who is recording the tale on paper, so the sentences are longer and more complex than they might be if one of the other "simple, good-natured" villagers were delivering the tale aloud. But Knickerbocker also brings a sense of oral storytelling to his writing with the idea that he is "telling" an audience the truth rather than recording it for readers. This style of narration positions "Rip Van Winkle" as a folktale that straddles the line between gossip and reliably recorded American history.
Irving includes a postscript, also narrated by Knickerbocker, that abandons storytelling conventions in favor of the style in which an anthropologist might document their observations about a newly-discovered place:
The Kaatsberg, or Catskill Mountains, have always been a region full of fable. The Indians considered them the abode of spirits, who influenced the weather, spreading sunshine or clouds over the landscape, and sending good or bad hunting seasons.
The region is the ancestral home of the Munsee people and other Indigenous groups. Like many anthropological accounts in Irving's day and beyond, the postscript emphasizes Indigenous traditions as ancient history that haunts white settlers in the region. This anthropological style reflects Irving's Romantic sense that a simpler past is slipping away. Nostalgic for the "lost" oral histories of the region, the postscript nonetheless embraces the settler-colonial notions of writing, modernity, and imperialism as inevitable advances in civilization.
Irving was by no means the first writer to ask readers to imagine that a folktale had been discovered in a scholar's anthropological writing about a rural region. The Scottish novelist Walter Scott's Waverley novels were growing wildly popular when Irving wrote the Sketchbook. More than almost any writer at the time, Scott asked readers to use his fiction to think about national history. Multiple frame stories, such as "Rip Van Winkle" employs, were a trademark of Scott's style, allowing him to play with the idea that history is never pure and unmediated fact. The epitaph to "Rip Van Winkle" further suggests that Irving was imitating Scott's style:
By Woden, God of Saxons, From whence comes Wensday, that is Wodensday, Truth is a thing that ever I will keep Unto thylke day in which I creep into My sepulchre—— CARTWRIGHT
Scott was known for starting chapters with epitaphs that steeped his novels in literary history. This quote at the beginning of "Rip Van Winkle" might be a nod to Scott as much as to Cartwright. It opens the story with the idea that everyone holds a piece of the historical truth, and that we all take a piece of the truth to the grave.