Bram Stoker’s original manuscript of Dracula included a preface that was cut before the novel was published in 1897. In this outtake, the creator of the world’s most famous vampire believed that he was not writing pure fiction: “I am quite convinced that there is no doubt whatever that the events here described really took place, however unbelievable and incomprehensible they might appear at first sight. And I am further convinced that they must always remain to some extent incomprehensible.”

Count Dracula was the literary culmination of two centuries of a resolute belief in the undead who walked among, and attacked, the living in eastern Europe. One of the strongest influences on Stoker, and other 19th-century authors, was the work of 18th-century Benedictine monk and distinguished biblical scholar Antoine Augustin Calmet. (Learn how vampires were scapegoats for disease.)

View Images A.A. Calmet (detail), in an 18th-century French engraving BNF

A valuable repository for vampire lore, Calmet’s two-volume supernatural survey, Dissertations Upon the Apparitions of Angels, Daemons, and Ghosts, and Concerning the Vampires of Hungary, Bohemia, Moravia, and Silesia, was published in 1746. The author carefully collected and examined numerous reports of vampire attacks that were emerging from eastern Europe in the late 17th and early 18th centuries. These accounts triggered an intense scholarly debate as philosophers and physicians alike sought to resolve the disconnect between the reports’ fantastic details and their reputable sources.

Calmet's case studies

Calmet acknowledged in his preface that the academic study of supernatural forces might invite criticism and derision, but he insisted that the testimonies from such reliable witnesses were too detailed and consistent to dismiss as pure delusion or outright invention. The validity of the various vampire reports, he insisted, merited careful consideration.

View Images An Old Obsession Belief in vampires and ways to eradicate them existed in the Middle Ages too. When epidemics struck, they were often blamed on vampires and “suspicious” corpses would be disinterred. Skeletons have been found with iron stakes driven into their chests. Skulls with large stones or bricks placed in their mouth have also been discovered—an exorcism technique believed to keep the corpse from eating its way out of the grave. NurPhoto/Getty Images

He documented many accounts of those who claimed to see the dead that “come back to earth, talk, walk, infest villages, ill use both men and beasts, suck the blood of their near relations, destroy their health, and finally cause their death.” These undead, he wrote, “are called by the name of vampires.”

One of the most famous cases in Calmet’s collection came from Austrian army surgeon Johann Flückinger. The doctor described the case of Arnold Paole, a soldier and alleged vampire victim from a Serbian village. To banish vestiges of the vampire, Paole ate dirt from its grave and smeared himself with its blood. He returned to his life as a farmer, but soon after died in a hay wagon accident.

About a month after his death, villagers claimed that Paole had risen from the dead and killed several people. Animals and livestock were also attacked and drained of blood. (Biologists found that vampire bats have vein sensors.)

Suspecting vampirism, the villagers exhumed Paole’s body. They found it intact—even the nails had grown. Fresh blood covered the inside of the coffin. The villagers thus “drove a stake through his heart, whereby he gave an audible groan and bled copiously.” The bodies of other villagers, thought to have been also transformed into vampires, were disinterred and likewise maimed in an attempt to “kill” them for good.

View Images Having been pierced through the heart with a stake, the body of a suspected vampire is “finished off” with a gunshot in a Transylvanian cemetery. 19th-century engraving White Images/Scala, Florence

Hair and nails

The incorruptibility of a corpse was thought to be evidence that a dead person was a vampire. Calmet noted that some bodies, after several months or even years in the grave, were found with “the blood in a liquid state, the flesh entire, the limbs flexible and pliable.”

The observation was accurate, but science rather than the supernatural can explain such postmortem phenomena. In large part, the belief in vampirism grew out of a lack of knowledge about the natural processes of decomposition after death, which can, under certain conditions, be delayed for a long period of time.

A body can remain well preserved through two natural processes; one of them, saponification, occurs when the body is buried in a cold, damp environment, as is common in eastern Europe. During the saponification process, the body’s fatty acids turn into a waxy, soap-like compound that covers the corpse and prevents putrefaction. A saponified body also retains a certain flexibility, as described in Calmet’s work.

Accounts in Calmet’s Dissertation also noted that vampires’ hair and fingernails continued to lengthen even after death. Certain postmortem changes may have given the illusion of continued growth. After death, the skin dehydrates, causing it to retract from the hair follicles. This may make the hair, especially stubble on the chin, look longer. The same is true of nails, as the skin around them retracts and makes more of the nail bed visible.

Blood of the vampire

Bloodstains on an unearthed corpse was also a sign that someone had become a vampire. As Calmet explained, “[Vampires] suck the blood of living men or animals in such abundance that sometimes it flows from them at the nose, and sometimes the corpse swims in its own blood oozed out in its coffin.”

Again, medical science can provide an explanation. The length of time that blood remains liquid depends on environmental conditions. In cold temperatures the blood can stay fluid for at least three to four days. If bodies were unearthed during that period on suspicion of vampirism, blood could still be found in their veins. Stories of corpses being stained with blood or “swimming” in blood (the latter likely an exaggeration) may have been derived from postmortem hemorrhages.

A blow to the body during transfer to its resting place can result in a trauma sufficient to make blood appear to flow from the nose or mouth. (A toothless vampire skeleton was uncovered in Bulgaria.)

Cry of the undead

As illustrated by the story of Arnold Paole, popular belief held that to kill a vampire, the corpse had to be disinterred and pierced with a stake. Allegedly, when the stake penetrated the body, the vampire would let out a cry, further proof that the vampire had been alive. But a natural explanation pertains to this too.

Air enclosed in the thoracic cavity, forced out when the body was struck, was likely to produce sound as it passed through the throat. Already believing they were face-to-face with an undead vampire, this noise could have sounded like a cry of pain to witnesses. In a situation of great tension, the imagination could amplify the slightest of noises to a blood-chilling moan.

In 1762 philosopher Jean-Jacques Rousseau incredulously attacked Calmet’s work. He noted: “If there is in this world a well-attested account, it is that of vampires. Nothing is lacking: official reports, affidavits . . . of surgeons, of priests, of magistrates. And with all that, who is there who believes in vampires?”

View Images An anti-vampire kit, made up of 19th- and 20th-century items. Royal Armouries Museum, Leeds Royal Armouries Museum/Alamy/ACI