Derrick, your rapier-sharp sexual innuendo is positively Austenesque, both in its wit and also in the penetrating insight of your observations!
I had never heard that tale of Edward II before, and surely you are right in suggesting (if I read you correctly) that JA was inspired by that ribald folktale, at least in part, to write her Carr-pet Sharade. I was inspired to do a bit of followup, and what I found is strongly supportive of drawing that inference.
First here is what Wikipedia has to say:
"The popular story that the king was assassinated by having a red-hot poker thrust into his anus has no basis in accounts recorded by Edward's contemporaries. Thomas de la Moore's
This suggests that the tale of Edward II's unfortunate end was in circulation as early as 4 centuries before JA would have read or heard about it. But here where JA's literary knowledge would have kicked in. Given that I believe (following and extending Jocelyn Harris's pioneering discoveries) that JA was very familiar with Chaucer's Canterbury Tales, I also think it very likely that JA would have made the association between this tale of the macabre death of Edward II, on the one hand, and Chaucer's "The Miller's Tale", on the other. In Chaucer's famous Tale, a very blackly comic romantic quadrangle, the
parish clerk Absolon takes his revenge on Alisoun's lover the student Nicholas by delivering a similar and very uncomfortable intrusion upon the rear end of Nicholas (but, because of its short duration, nonfatal in that instance). There's no way that JA failed to see this linkage.
And, thinking about that made me quickly realize that the source for Chaucer's choice of that sort of karmic revenge on Nicholas must itself have been that very same tale about Edward II's death, given that Chaucer was born a mere 13 years after the death of Edward II, and would therefore have composed the Miller's Tale in part in reaction to that account of barbarous regicide. And a quick Google search confirmed that I am not the first to spot that ghoulish parallel:
_The Canterbury Tales Revisited – 21st Century Interpretations_ (2008)
P. 16 et seq.: "Queer Punishments: Tragic and Comic Sodomy in the Death of Edward II and in Chaucer’s Miller’s Tale" by Kathleen A. Bishop
So what I see is Chaucer writing "The Miller's Tale" in part as a not so veiled allusion to the death of Edward II, and then I see JA reading both Chaucer and historical accounts of Edward II's death, and realizing they are the same, and then adding her own layer to this ongoing "conversation".
And then I found this:
It's interesting that the man who wrote the above debunking article is named Mortimer--hard to imagine that he would be trying to protect the family name, 700 years later!---but I mention this because I don't think it matters at all whether the story was apocryphal, in terms of JA's riffing off it--what matters is whether it was a story in circulation in JA's time, and she knew about it, and saw Chaucer's hand in the mix, and decided to join the parade.
One last point--I was curious to see if I could find any published sources contemporary with JA's life where the tale about Edward II's painful death was mentioned, and here is the only one I found:
_An Epitome of Juridical or Forensic Medicine_ by George Edward Male (1816), at P. 10, in the midst of a rather matter-of-fact discussion of the recommended procedure for an autopsy following discovery of a corpse where nothing is known as to the cause of death:
"...The other abdominal viscera, and the whole length of the intestinal canal, should be traced, as it is possible that hernia, introsusception, or inflammation, may have been the cause of death; an empoisoned clyster may have been administered, or (as in the case of king Edward the Second) a hot poker or other instrument thrust up the rectum. ..."
Even though I did not find a published source contemporary with JA's teen years, for the reasons set forth above, I am convinced that Derrick was spot-on in connecting the dots from JA's Carr-pet Sharade to the perhaps-apocryphal tale of Edward II's painful death, it only adds to all the long list of veiled allusions to male homosexuality which populate JA's novels.
P.S.: Now whether Mitford had any of the above in mind when she wrote the following in 1813, that remains to be seen:
"[JA]was no more regarded in society than a poker or a fire-screen, or any other thin upright piece of wood or iron that fills its corner in peace and quietness. The case is very different now; SHE IS STILL A POKER—BUT A POKER OF WHOM EVERY ONE IS AFRAID."