Spiritism is a philosophical doctrine established in France in the mid 19th Century by the French educator Hippolyte Léon Denizard Rivail, under the pseudonym Allan Kardec. The term was coined by him as the specific name of the doctrine he was about to publish but, given the fact that the word was created from roots taken from the common language, it was soon incorporated into the normal use and has been used to name other doctrines as well, though the original Spiritists protest against this usage.
Spiritism Through History
Mediumship and other phenomena studied by Spiritism haven't been "created" by Kardec nor are properly recent. They existed since the dawn of mankind, having manifested in most primitive religions, but being more closely related to Shamanism. Most other religions, however, contain them in some degree. The Catholic worship of the saints, for instance, is likened to the veneration of the enlightened spirits. The manifestation of the Holy Ghost in Pentecost is explained by Spiritism as a mass manifestation of mediumship.
Most Eastern religions (and some ancient Western ones) reserve a central role for the worship, or the veneration of the ancestors (For this reason, Spiritism has found great resistance outside the West. Actually, it has remained restricted almost exclusively to Brazil).
In Ancient Greece it was believed that the dead inhabited the Hades and that it was possible to reach them, either by mediumship or by a type of astral projection. Ulysses and Orpheus are two characters who went to the Hades eventually. In the Iliad, Achilles and Ulysses also used a bloody sacrifice to summon the souls of the dead.
In the Middle Ages, as an influence of the Germanic peoples, it was believed that the dead could eventually come back and haunt persons or places; this being the origin of the legends of ghosts and haunted houses.
By the time of William Shakespeare popular belief on ghosts was widespread in Britain and he used them as plot devices in several of his works, like Hamlet, Julius Caesar (play) and Macbeth.
Asian Shamans claimed to have fully accomplished the ability to communicate with the dead and the gods and served as intermediates between them and the living people. American Native medicine men also claimed the same ability.
Spiritism and Christianity
Christianism has been traditionally critical of Spiritism, mostly because the Mosaic Law clearly forbade the Jewish people all forms of communication with the dead (Deut. 18: 10-14). Some Christians hold that the supposed spirits of the dead are actually fallen angels, while others claim that the clear rendering of scripture teaches they are demons.
Most of the Christian opposition to Spiritism is found among Evangelical Christians who believe salvation is a free gift of God, which we are unworthy of. Contrary to this, Spiritism states that all spirits will eventually attain full illumination. Christian Fundamentalists also reject spiritism following the Mosaic Law on the subject.
The Catholic Church clearly forbids its members to take part in mediunic sessions, or any type of reunion concerning the evocation or the communication of spirits. Most religions have a similar position, however, depending on the country, there seems to be more tolerance towards spiritism. This is especially observable in Brazil.