Necromancy : The magic of communicating with the souls of the dead

Necromancy is the magic of communicating with the souls of the dead for the purpose of obtaining useful information. The word literally means corpse (nekros) divination (manteia).
It is one of the most ancient forms of magic. A large part of primitive shamanism, from which all forms of magic derive, was about communicating with the spirits of dead ancestors. We see this in modern Voodoo, which is essentially a religion of ancestor worship that has evolved a pantheon of gods and goddesses who fulfill the roles of great ancestors to all the people.
What sets necromancy apart from ancestor worship is its attitude toward the dead. The necromancer communicates with any easily-accessed soul that may possess the information he or she needs, and the willingness of the departed is of no consequence. Necromancers compel the souls of the dead to reveal their secrets against their wishes.
Traditional necromancy relied upon the relics of the corpse as a bridge to establish communication with the shade of the dead person. It involved the use of such things as grave mold, the bones, skin, hair and fingernails of corpses, and body parts such as hands, teeth and eyeballs. The skull was considered to be especially useful, since it housed the organs of the higher senses of sight and hearing, the senses through which the dead person acquired secrets.
A departed soul might be expected to know important matters in two areas: what he had seen or done during life, and what he had seen or done after death. Often necromancers called up a shade to discover the hiding place of treasure which the person during life was rumored to have possessed. The dead were thought to have special access to occult knowledge, and sometimes they were called back from beyond the grave to teach the necromancer techniques of magic not available by any other means, techniques acquired in the afterlife.
It was believed that the shades of the dead were attracted to freshly-spilled blood, because blood was one of the primary repositories of vital energy in the body. Since the dead lacked bodies of flesh, the thinking went, they must lack vitality and therefore be weak. Hence their pale appearance when they were seen as ghosts. If fresh blood was spilled while still warm on the ground, or better still into a pit, or even better still into the opening of the grave, its energy would attract shades, who would then seek to nourish themselves upon on.
The reason it was better to spill blood into a pit is that in ancient times in Greek and Rome where necromancy was extensively practiced, the underworld was popularly considered to lie beneath the ground. Spilling blood into a pit brought it nearer to the shades of the dead and drew them upward. It was sometimes spilled into the grave of a specific individual to attract that soul, on the theory that the shades of the dead have an affinity with their own corpses.
Murderers and other criminals executed for their crimes were prime targets of necromancers, both because there was seldom a loving family to tend and guard their remains, and because anyone executed as a criminal was thought to have a restless spirit that walked the earth, and therefore was more accessible.
The common image of a necromancer shows him or her confronting the actual risen corpse that has been animated and made to stand and walk through magic. This is, of course, mere fantasy, but at its root lies the true practices of necromancy. The corpse was not actually made to move and speak. It was merely used as the focus for the spirit attracted by the spilled blood and evocations of the necromancer. It was necessary for the necromancer to possess mediumistic abilities to hear psychically the words of the spirit, or to gain the information of the spirit through other forms of communications. Oftentimes the shade of the dead, called up by the necromancer, merely pointed in the direction where his treasure lay buried, or silently led the necromancer to the spot.
In my opinion, it is not possible to call forth through necromancy the actual souls of those who have died. However, it is possible to summon spirits who represent themselves as those departed human beings to the necromancer, and these spirits may indeed possess valuable occult knowledge, or know of things that are hidden.
There are two necessary aspects to necromancy. The calling of the shade, and the compelling of the shade. In ancient times these were combined. For example, Odysseus, the hero of Homer's Odyssey, called back shades from the underworld by spilling the blood of sacrificed beasts into a trench in the ground, then compelled the shades to speak by preventing them with his drawn sword from drinking the vital essence of the blood. Spirits are vulnerable to cold steel.
You may say that the Odyssey is only a fable. True, but in the age of Homer there were many necromancers in Greece. Homer was an intelligent and well-informed man. His description of necromancy is very probably based on the actual practices of Greek necromancers.
A shades can also be summoned by establishing a magic link with it using a relic from its corpse, and then inflicting pain upon the shade through the relic until the shade complies with the demand of the necromancer. For this reason, the shade is often very unhappy with the necromancer, who usually works inside the protective boundary of a magic circle so that the shade cannot attack him. You can see such a magic circle in the illustration at the top of this page, which shows the Elizabethan alchemist Edward Kelley, and his friend Paul Waring, together inside a magic circle confronting a corpse in its grave shroud, which they have evoked by magic. This is a depiction of an actual event - Kelley was a necromancer in addition to his alchemical pursuits.
Given the nature of necromancy, it is not to be wondered that necromancers were shunned by the general population, and were forced to live by themselves, often in the near vicinity of graveyards, where they procured the materials for plying their trade. They were only sought out by those who desperately needed information that could not be obtained in normal ways, and were handsomely paid for their services.
Not only graveyards, but gibbets and battlefields were popular haunts for necromancers. A gibbet is a structure like a gallows from which the bodies of executed criminals were hung until they rotted, were pulled apart by crows and ravens, and fell to the ground. Beneath a gibbet, which was usually on a road removed at some distance from the town since rotting corpses stink, the necromancer might expect to harvest many useful bones. If he or she was more bold, parts of the corpse such as the hands would be cut off with flesh, fat and skin still attached. All these materials are useful in necromancy.
Battlefields were popular with necromancers because the ground was literally saturated with blood. In previous centuries wars were fought with swords. Sometimes soldiers struggled ankle deep in blood. Since this was the place of their deaths, the restless shades of slain soldiers were believed to haunt any field where a battle had been fought. This made a battlefield, particularly a recent battlefield where the blood was still fresh, an even better place to work necromancy than a graveyard.
Necromancy was not solely man's work. There were female necromancers in ancient Greece and Rome, who are usually referred to, under the much abused umbrella term, as witches. The term witch has been far too broadly applied in English texts to anyone who worked, or was believed to work, evil by magic. Necromancy was a very specific type of magic, as I have indicated, and was not necessarily always worked for evil purposes.
Because traditional necromancy used blood and corpses, and was worked in places where people had died, been executed or lay buried, it was universally abhorred and condemned. If for no other reason, it should be outlawed because it desecrates the remains of the departed and causes grief to the families of the disinterred or otherwise disturbed bodies. It is one of the darker and more sinister branches of Western magic, best left sleeping in the past beside the shades of the dead.
 
Source : http://www.donaldtyson.com