Brain Snacks: Tasty Tidbits of Knowledge
Unlike most of the other Romantic poets, Keats had no formal literary education and actually had a day job for a while. He was trained as a surgeon (which didn't require a university degree back in the day) and during his lifetime was regarded by the snobbish mean girls of the literary world (read: basically everyone in the literary world) as a lower-class upstart. (Source.)
If you thought the "throbbing star" bit was a little too much, just think: this poem used to be steamier. When Keats sent off his first draft to his editor, John Taylor, Taylor sent it back to him and told him to take the sexiness down a notch or two so as not to offend the ladies. Keats's response? "He says he does not want ladies to read his poetry:—that he writes for men." He nevertheless tweaked some bits, and the final version has less panting and fewer mentions of Madeline's "bursting bodice" and "bosom bar." Alas. (Source)
Because everybody needs a little nineteenth-century fan-fiction now and again: St. Agnes was a character in the 1893 historical fiction novel Fabiola which—surprise surprise—is all about martyrs. (Source.)