“A White Heron” is set in rural Maine in the 19th century. The setting is extremely important to the story—New England, at the time that Jewett was writing, was just starting to become a site of rapid industrialization. While many people were moving from rural communities to towns for manufacturing jobs, the character of Sylvia does the opposite, leaving her family in the city to move in with her grandmother Mrs. Tilley in rural Maine.
Jewett intentionally opposes the negative effects of living in an overcrowded city with the enlivening effects of living in the woods or countryside. This comes across in the narrator’s description of Sylvia early on in the story:
There never was such a child for straying about out-of-doors since the world was made! It was a good change for a little maid who had tried to grow for eight years in a crowded manufacturing town.
Here Sylvia is a stand-in for New Englanders (and even humankind)—she is unable to “grow” in a manufacturing town and thrives while being outdoors. Jewett is hoping that readers will remember how people, for most of human history, lived in small communities in harmony with nature. Living in cities, on the other hand—at least according to Jewett—signifies the destruction and degradation of nature.