Violent Ends (Violent Delights Book 19)

Afterword for Part 2

HV's death is actually rather well documented, however, his cause of death technically remains unknown. But, before we get into the theories, accuracy of the narrative.
Everyone's locations, and Henry's crimes listed, are true. His atrocities at Meaux, Rosen, and Cean, are accurate. He was apparently quite fond of animals, involving his three favorite war horses in his funeral, and he bred English Mastiffs, so it's likely he had some about.
Henry's last words are accurate. He also did a lot of paperwork prior to his death, very in character, even asking doctors how long he had so he could get more done. It's true he didn't summon Catherine nor did he mention her in his final arrangements.
It is also accurate that before death, Henry cried out (in his sleep) 'Thou liest! Thou liest! My portion lies with Jesus Christ!" As if haunted by an unseen demon. This is the inspiration of the Bastard's haunting of him.
If you're thinking 'wow this all sounds familiar, haunted on the eve of death by ghosts/demons and using physiological warefare with a dagger offering to be killed' then you're right. Shakespeare gives these fun little anecdotes to Richard III in his play, giving Henry V all the glory. But those do technically make to page, albeit ascribed to another king. Henry crying that out is recorded by his chroniclers, it's not just rumor, so it likely happened. (I have an entire theory that Shakespeare ascribed some of Henry's more villainous aspects to Richard III, Henry was the more Machiavellian, Henry married with little intent of loving his wife, Henry was in fact the one who was disfigured on sight, the arrow wound made him much worse to be hold than Richard, who had blue eyed and dark hair and only a slight shoulder stoop, it's Henry who put a dagger to his own chest as a form of manipulations albeit with his father not his betrothed, it's Henry who had his heterosexual-life-partner stir up crowds for him and spread rumors, and it's Henry who was haunted the night before his death).
Sadly, little is known about the Bastard of Varus, beyond his role at Meaux. He's generally regarded as a villain, despite being instrumental in causing Henry's death and ultimately stopping his march across France.
Obviously, Courtenay is to this day buried with Henry, in a crypt beneath Henry's tomb. Whether or not this was public knowledge at the time is debatable. Given someone like Beaufort probably did the burial rites, and the crypt was made people did know about it, but with no marker no contemporary remarks regarding a blood brother burial thing, it seems Henry did keep it a bit of a secret.
And now, what did Henry actually die of?
His symptoms are as described in the novel. Apparently, he lost weight so drastically, that he lost muscle mass as well, to the point that when he died some accounts say he wasn't even disemboweled as there was nothing left to decay. Some accounts say he had 'St Anthony's fire' which would be some sort of skin inflammation. He's described as having the flux, unable to keep food down, and being in severe pain, to the point where he fell from his horse after trying to ride.  Some accounts say his legs and belly were swollen from fluid. At the end of his life he had a very high fever, and doctors said they could do nothing for him.
He first summoned a doctor at Meaux, but dismissed him the next day. He later summoned a doctor mid June. Then in July he was laid up for a couple of weeks, went to war on a litter, but took a turn for the better.
Then come August he fell from his horse, admitted he needed care and retired to the castle where he died three whole weeks later. So, he had symptoms for two months.
All in all, his symptoms are those of a terminally ill man. And so, the theories
Flux/dysentery this is most commonly cited. However, while he may have had complications of intestinal upset, or even contracted the bacteria which weakened him, flux either doesn't kill you with basic supportive care, or attacks kidneys causing death within a week (as happened to Courtenay). Ergo, he didn't have a flux for three months, maybe
Small pox/St. Antony's fire. Apparently his army did have small pox. However, it's highly unlikely a grown man lived three months with small pox, passing none of it to his brothers or companions, and then finally dying of it after three weeks of bedrest. Henry was quite healthy most of his life. He'd been campaigning hard but he did seek doctors he knew he was ill.
Congenital/chronic illness. This is most likely in my opinion. Diabetes or heart failure would cause, in end stages, rapid weight loss. Simply put they wouldn't have known at the time if he had something like that, or even hyperthyroidism. Highly treatable now, but debilitating at the time. It would explain his slow descent, he knew he was ailing, he identified symptoms. And simply put, after he was weakened from a chronic illness he could have contracted flux or pox which weakened him further, or a bacterial infection due to his lowered immune system. Again, I think this is most likely given the extreme weight loss.
Marfan syndrome. Lionel of Antwerp, John of Gaunt's elder brother, is believed to have had Marfan syndrome. Lionel grew to seven feet tall and died suddenly in the night, affected individuals often grow very tall and are unusually lean. Marfan syndrome has a host potential symptoms including heart trouble manifesting often in adulthood. Lionel died in his early thirties. Marfan syndrome is inherited. Henry would, like his great uncle, would be unusually tall at six foot three, and was noted by many to be unusually lean. By unusually lean, a knight like Henry should have been quite muscular, from wearing hundreds of pounds of armor to horse back riding. So if Henry remained quite thin, given he ate well, it was unusual.
Some other congenital illness. The Plantagenet family line after Edward III had a high male mortality rate in the early thirties to forties, of illnesses that remain unspecified, but led to no loss of cognitive function. The Black Prince fainted and was ill for years before dying in his forties, and he and John of Gaunt would both have sons die young, Lionel of Antwerp and Thomas of Windsor would both die in thirties in the night. Was something inherited?
On the same token, Henry's IV, V, and VI all would, in their thirties, fall seriously ill. All three men would become dangerously ill, with unspecified symptoms of collapse or pain. H4 and H6 would both recover within eighteen months, with no loss of cognitive function or explanation of their illness, and both would live several more years mostly recovered (handling business, walking, riding, etc). H5 would die, however, he'd been under much more strain, on campaign for months with possibly a pox or flux also affecting him due to his lifestyle, his father and son, though they too would fall dangerously ill, were both at home at the time and had been living comfortably. Did they all have diabetes or a heart condition or something that, with even lucky supportive care H4 and H6 shook or were able to home medicate essentially, but H5 didn't because they couldn't raise his blood sugar or something due to complicating conditions?
STD, I put this on here but I don't think it's likely. I refuse to believe Henry got close enough to anyone to get an STD. Just kidding, however there is an important point here. H5 was the only one of the four brothers to have a legitimate child, despite all four brothers marrying. Now, Henry's lack of interest in his wife is explained by his usual asexuality, however that doesn't explain his brothers who wed women who either had children or went on to have children. Were all the brothers carrying an STD contracted at a young age from their father (that's not creepy, men kissed on the mouth as a greeting, they all had something if one had it, and we truly believe H4 had STDs), and that is why they had no children? Something similar to HIV could remain dormant, and many STDs cause infertility.