"The Yellow Wallpaper" was first published in 1892, & made it into our anthology in 1989, in the 4th edition. Unlike The Awakening, it wasn't out of print all that time, but until the 1980s it was read as a Poe-esque tale of madness. Feminist critics taught us to see that the madness Gilman is exploring had socio-cultural origins.
Gilman herself said she wrote the tale as a protest against the "rest cure" as a treatment for mental illness, based on her own experience of such a "treatment" at Dr. S. Weir Mitchell's aslyum in Philadelphia in 1887. His recommendation that she "live as domestic a life as possible" sent her, as she put it, "so near the borderline of utter mental ruin that I could see over." CPG spent her career writing and speaking about the oppression of women. Mitchell treated men as well as women, & it's curious that CPG never explicitly linked her indictment of his methods to gender politics, but clearly modern readers are right to see how surreally close the "rest treatment" (stay home, don't work, be passive) was to the domestic role enjoined on upper class "ladies" for whom CPG lectured & wrote. The genteel role of "lady" has a lot in common with that barred nursery the narrator of "YW" is confined to. And the relationship between her & John, her husband & doctor, is a kind of surreal dramatization of the patriarchal ideal whereby the man not only tells his wife what to do, but what to think, how she feels, etc.
That's where the narrator begins -- having internalized that voice of authority, at odds even with what she "would say" (p. 667) & forced to feel her self, her own feelings, as diseased. Two things happen in the story. She commits herself to the task of exploring the wallpaper, of tracing its pattern "to some sort of conclusion," and she decides, despite the taboo against it, to write, to express her self. The wallpaper & the paper on which she's writing are scenes of a similar "progress" -- looking at the wallpaper, she sees what it expresses more & more clearly: the figure in it (p. 670) is identified as a woman (672) who's struggling to free herself from the lines of the paper, which are really bars (674); she's one of many women so confined (675), all of whom are victims of an oppressive & strangling pattern (676). These "revelations" are also bringing her closer to the truth of her own life, esp. her relationship with John -- the "dear John" who "loves me very dearly" (672) is in fact her antagonist who only "pretends to be loving and kind. As if I couldn't see through him!" (676)
In this process she begins to assert her self -- "but I am here" (677) -- yet the deep ambivalence of the story (and the reason I put "progress" in quotation marks above) is that the more of the truth she sees, the madder she becomes, because, the story seems to suggest, the truth of her "condition" as a woman is unbearable: seeing it doesn't so much make her free as drive her completely crazy. These are pretty modern ambivalences: the "reality" of this woman's life, as defined by social conventions & her husband's lack of sympathy, is mad; her madness is a form of what Dickinson calls "divinest Sense"; yet seeing that apparently leaves her no where to go except deeper into madness. She triumphs over John & his chauvinist presumptions (at end he "swoons," like a woman in a conventional romance), but can't (to me) be said to triumph herself, left as she is creeping around & around in a circle . . . although we did briefly consider another, more positive way to read that ending: at the very end the narrator dismissively refers to "Mary," who may be her own earlier self, John's submissive wife, and that may suggest the birth of a "new woman," who has broken free of the patterns that constrained her, whose "creeping" (i.e. crawling) in a nursery would be only a beginning (we all had to crawl before we learned to walk), and not the end.