I read this story (IIRC novelette length rather than "short story") about 10 or so years ago, probably in a collection.
It is a hilarious spoof of an academic article. This "article" is about an American poetess of the XIX° century. I remember that at that time I did check that the poetess has really existed, but I forgot who she was. On Wikipedia there are 63 pages under "American poetesses of the XIX° century" and I gave up checking each and everyone one's biography. Besides though she did exist, her real biography might differ from what I remember of the story.
The paper is written as an academic paper with lots of notes. IIRC, the notes represent about one third of the total length of the "paper". The author claims that the invasion by Martians described by H. G. Wells actually took place, but that Wells was wrong about the reason (terran microbes) of its failure. According to the author, a Martian projectile had hit the ground near the cemetery where the poetess had been buried. The shock wave both exhumed her and "woke her up". This is all the more ridiculous as the paper does mention the (correct, I did check it when I read the book) year of the poetess's death and that was decades before the year that Wells has claimed as that of the "invasion". Thus awaken, the poetess then started to write poems (which, at the time, I also did check as really written by her) while lying in her reopened grave. The author claims she had always pencil and paper on her, and was buried with them.
The author of the academic paper rejects the generally accepted year when those poems where written, namely, of course before the poetess's death, and gives totally ridiculous readings, usually of isolated sentences, to make them refer to the "invasion by Martians", and therefore, posthumous, or rather, post-exhumation. Moreover, these readings are interpreted as threatening the Martians to frighten them away. Or maybe, so boring as to convince them to flee from a planet where poetry was so bad and thus hurting their delicate sensitivity. Or, IIRC, both. The seriousness with which all this utter nonsense is constructed on excerpts of poems actually written by her is a masterpiece of humour.