Date of Discovery

Linguistically speaking the etymology of the word Nightmare dates back to the 1300s, but the phenomenon has been under investigation as far back as the second century.

c. 1300, “an evil female spirit afflicting men (or horses) in their sleep with a feeling of suffocation,” compounded from night + mare (n.3) “goblin that causes nightmares, incubus.” The meaning shifted mid-16c. from the incubus to the suffocating sensation it causes. Sense of “any bad dream” is recorded by 1829; that of “very distressing experience” is from 1831. Cognate with Middle Dutch nachtmare, German Nachtmahr. An Old English word for it was niht-genga. – “Nightmare”


The Nightmare is a type of demon that is also known as a Night Terror, Night Hag, and Old Hag. Unlike the named demons that make up the commanding force of demonic entities, these lesser demons are known only by their function.

Physical Description

Although there isn’t a consistent description of the Nightmare, the various descriptions throughout the history of the demonic entity suggest that it can take a variety of forms. In most cases, the demon presents as an invisible entity, although there are reports of it being a dark shadowy figure or an inhuman and demonic shape. Most reports indicate that its breath can be heard as a low rasp, it possesses glowing red eyes, as well as a strong revolting odor that fills the room in its presence.


The best guess on where the Nightmare originated is second-century Greece when Galen of Pergamon first investigated the phenomenon.

Mythology and Lore

As can be assumed by the name, the Nightmare attacks mostly at night but is known to do so at any given time during the day or night. Within the paranormal community, the Nightmare is often confused with poltergeist activity, and in rare cases has been associated with vampire attacks. The Nightmare is also related to the Mara (also known as a succubus), another type of demon that attacks humans at night, with the ultimate goal of sexually assaulting them.

As a typically nocturnal influence, the nightmare strikes people when they sleep, often causing the individual to experience strange smells, sounds, and images, then causes suffocation and a phenomenon known by the scientific community as sleep paralysis. Other characteristics are varied from case to case but remain a consistent variable when taking into consideration all of the reported attacks. These cases involve the individual waking from a deep sleep unexpectedly to the sensation of an unseen entity sitting upon their chest—the individual’s attempts to move, struggle, speak or scream are futile, which is understandably the most frightening aspect of the attack. It seems the Nightmare’s purpose is not to kill, as the attack ends just before the individual passes out. The victim typically recalls all details of the alleged attack the next day and demonstrates a prolonged sense of mental, emotional, and physical fatigue.

In some reported cases of a Nightmare attack, victims are awakened to audible footsteps approaching them as they lay in bed, while there is no figure to attach the footsteps to, they immediately feel the effect of being paralyzed, likely due to extreme fear.

Nearly 15% of the adult population worldwide has reported having at least one attack from a Nightmare within their life, according to modern research. Documented in second-century Greece, physician Galen of Pergamon analyzed several patients who reported having nightmares but attributed the phenomenon with indigestion. While it’s still often proposed as an explanation for individuals reporting such cases to their doctors there are a couple of other theories that have been developed since—commonly, sleep disorders such as narcolepsy, as well as the rare case of repressed sexual tensions. Suffice it to say, these explanations may be accurate for some of the cases, but it does not satisfy them all.

During the Middle Ages, when circumstances such as this were being investigated, it was normal for the explanation to be something supernatural, such as witchcraft to be the cause. In fact, the names, “Night Hag,” as well as, “Old Hag,” refer to an older term for witches, “hag.” Witches were believed to come into a victim’s house at night and then, “ride,” a person’s chest at night, causing the victim to feel as if they were being suffocated, then exhausted the next day. This is actually where the term, “hagridden,” was born, to indicate a feeling of being run down, or exhausted. It was also common for individuals to accuse witches of attacking them magically, by cursing them and sending a demon to attack them. It was a common belief that a religious object held close to the body, or an amulet worn around the neck would ward off any potential Old Hag encounters.

Modern Pop-Culture References


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Telling the Difference Between Demonic Entities

Horror Mystery and Lore

Possession movies, even when they are highly religious in context, bring in huge crowds of fans, starting with The Exorcist (1973) and continuing on throughout the years, we never really get down to the brass tacks of demonic entities, who they are—or might be—and the people they have affected. Demon lore is complex in every religion and affiliated culture, there are elaborate organizational schemes for demons dated back from the 16th and 17th centuries and yet we still have so little understanding of them. For the many ills and misfortunes that plague the human race, there is the possibility of a demonic association that leads to exorcisms in many cultures. Specifically, in Catholicism, exorcisms deal with demonic possession, in which demons are said to battle for control of the soul of the victim they have targeted, these practices date back to 1614.

The Demons that Invade Our Lives

Christian demonologist Johann Weyer estimated that there were nearly 7.5 million demons that served as minions to 72 different princes of hell. Each of these demons belongs to a class of demons; to name a few, there are demons that attack people in their sleep, drain vitality, or possess those who are struggling with their own identity. So, let’s take a look at the different types of demonic entities that go beyond the typical Catholic exorcism expectations.

Attractive demoness
Photography by Alice Alinari

The Succubus

During the Middle Ages, authorities within the Christian religion asserted the existence of sex demons, which they furthered that to insinuating that sex with such demons was a sign of witchcraft. Although it’s a widely accepted possibility in the paranormal community, the stories and theories of such acts are described as horrific to experience. To be clear, while this may sound like an exciting ride for some lonely people out there, it’s not something that anyone in their right mind would purposefully pursue—it’s never consensual.

The Djinn

Collection of Genie Lamps--don't summon a Djinn!
Photography by Louis Hansel

Between 100 and 400 AD, the Testament of Solomon was written, which served as a list for Hebrew, Greek, Assyrian, Babylonian, Egyptian, and Persian demons. The Djinn are self-propagating, malicious, yet mortal demons. They are an invisible creature by nature but have shape-shifting abilities so they may better stalk their prey. Solomon was able to control these types of demons which he called djinn with his magical ring and he would frequently treat them as his own personal slaves by making them transport him wherever he wished upon their backs.

My Dream, My Bad Dream, Fritz Schwimbeck, 1915. Fritz Schwimbeck
My Dream, My Bad Dream, Fritz Schwimbeck, 1915.

The Nightmare

The story of this nocturnal visitor originated in the ancient world, in which a spirit or demon would come into the room of its sleeping victim, male or female, to incapacitate the individual and feed off of their vitality. In all reported cases, it is said the victim awakens to either a heavy weight on their chest or one that starts at their feet and progresses to their chest, either way, they are unable to move out from under the weight of the night hag. As they’re feeding off of the individual, the victim feels as if they’re suffocating and paralyzed, despite being fully conscious. Victims of the night hag end up reporting feeling groggy, sick, and otherwise exhausted both mentally and physically the next day.

Western-style vampire bears her fangs.
Photography by Rondell Melling

The Vampire

Now just wait, you’re probably conjuring up an image of Dracula hunched in a dark window of his castle in Transylvania, brooding and dangerous. The concept of the vampire in modern culture, especially since Stoker’s rendition, are the undead who return to kill and torture the living, but the actual origin is somewhat different. Older than the Slavic version of Dracula is a supernatural and demonic entity that did not actually take human form and it spans the world with small variations.



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