He knows I have a weakness for the atmosphere of Victorian genre fiction, from Raffles relieving the aristocracy of the burden of wealth to pissed-off ghosts chasing M.R. James's bumbling antiquarians. Who can resist an era in which first aid for any trouble begins with a shout of, "Brandy! For God's sake, bring her some brandy!"
Michael Sims looks at the origins of Victorian vampire tales, including origins in natural and social history, specifically the facts that "often people in the 18th century had an opportunity not only to see corpses but also to glimpse them again after they were buried" and "no one understood the process of decay within a subterranean chamber."
I wondered: If ordinary people were encountering the corpses of the recently dead or even long-dead friends and relatives, what were they actually seeing that they misinterpreted and then wove into a vampire mythology?
Many natural changes after death were judged to be evidence that the late lamented had turned into a bloodsucker. Like hair, fingernails don't actually continue to grow after death, but as fingers decompose, the skin shrinks, making the nails look abnormally long and clawlike.... Dead skin, after sloughing off its top layer, can look flushed and alive as if with fresh blood..... In one eyewitness account from the 18th century, a vampire is even found—further proof of his vile nature—to have a certain region of his anatomy in a posthumous state of excitement. The genitals often inflate during the process of decomposition.
And what about the blood reported around the mouths of resurrected corpses?... Many bodies were buried face down, resulting in blood pooling in the face and leaving it looking flushed. Sometimes blood also gets lifted mouthward by gases from decomposition. Vampire stories recognize that death is messy.