Washington Irving is an interesting writer to apply this kind of question to, given that so much of his writing is itself suspended between the colonial and post-Revolutionary eras. Born in 1783, he was part of the post-Revolutionary generation, and one of his central thematic concerns (perhaps most strongly expressed in stories like "Rip Van Winkle") was an attempt to explore the question of American identity, and the transition (and continuities) between colonial rule and independence.
Be aware, "The Legend of Sleepy Hollow" was originally published in 1820, and the United States at this time was not yet a fully modernized or industrial powerhouse (as it would become in the second half of the nineteenth century), but was only in the very beginning stages of that transition. This story was written in the era of the Lowell Mills and the construction of the Erie Canal, not the era of Standard Oil and the Railroad Pools.
In any case, one of the interesting and powerful dynamics within the story lies in the sense of continuity it sketches within its setting. This story is set in 1790, in the era soon after the Revolutionary War, and yet life very much resembles the kind of pre-modern existence one might associate with even a century earlier. There is none of the energy and democratic zeal that characterizes the townsfolk of "Rip Van Winkle," but instead what we see is a far more parochial existence, and a purely agrarian way of life. This sense of timelessness, of a way of life largely untouched by modernity, is conveyed by Irving himself, even before he introduces the character of Ichabod Crane, when he writes:
I mention this peaceful spot with all possible laud, for it is in such little retired Dutch valleys, found here and there embosomed in the great State of New York, that population, manners, and customs remain fixed, while the great torrent of migration and improvement, which is making such incessant changes in other parts of this restless country, sweeps by them unobserved.
This same sense of suspension is interestingly reflected in the character of Crane himself.
It's notable that, though Ichabod Crane is the most well-educated member of his rustic community, his mindset is itself very much pre-modern. Keep in mind, intellectually speaking, the American Revolution was a movement founded in the Enlightenment and rationalism. Crane, on the other hand, is very much superstitious, believing in all manner of supernatural effects. It is not by accident that, when establishing Crane's erudition, the specific book which Irving cites is Cotton Mather's book on witchcraft. For all his education and role within the community, Crane himself is, even within the standards of his time, a representative of the mentality which the Enlightenment aimed to overthrow, rather than of the post-Enlightenment mentality which the Revolution was a part of.
And yet, for all that this setting continually hearkens back to the pre-Revolutionary and, perhaps more importantly, pre-Enlightenment world, it is squarely placed within a post-Revolutionary timeline, particularly in its local legends and stories:
There was the story of Doffue Martling, a large blue-bearded Dutchman, who had nearly taken a British frigate with an old iron nine-pounder from a mud breastwork, only that his gun burst at the sixth discharge. And there was an old gentleman who shall be nameless, being too rich a mynheer to be lightly mentioned, who, in the battle of White Plains, being an excellent master of defence, parried a musket-ball with a small sword, insomuch that he absolutely felt it whiz round the blade, and glance off at the hilt; in proof of which he was ready at any time to show the sword, with the hilt a little bent. There were several more that had been equally great in the field, not one of whom but was persuaded that he had a considerable hand in bringing the war to a happy termination.
Certainly, the most notable of these local legends is the legend of the Headless Horseman himself, a Hessian soldier killed in the Revolutionary War.
In this sense, one might get the sense that the setting of this story is one which is being pulled in two different directions. It concerns a rustic community, one whose shared mindset and lifestyle directly hearkens back towards the pre-modern era, even as the memory and dynamics of the Revolutionary War remain in place, given that this is a community that is established as having directly experienced the conflict.