Concerning demonic possession, it would seem that one needs to believe in a particular possessing entity in order to be possessed by it. That is: Christians need to believe in the Devil and his demons to become possessed. Possession by evil, damned spirits and fallen angels – by “the Devil and his minions” – is nearly unheard of outside of Christian cultures. It’s like reincarnation: in cultures that deny it, reincarnation is said rarely to occur, while in cultures that affirm it, reincarnation is said to occur with some regularity.
If memory serves, there is a Jewish tradition of demon possession derived from very ancient times, but still, Jewish demons are not “Christian” demons, and the Christian horned bogeyman is never said to possess Jews – as far as I know. However, Jewish tradition does mention the dybbuk, or possessing spirit of someone who has died – a soul who possesses. In William Peter Blatty’s Legion (sequel to The Exorcist), the Jewish cop Kinderman wonders about Christian demon-possession in contrast to Jewish dybbuk-possession. In the Middle Ages, ancient Jewish demonology shook hands with Christian demonic speculation and became Magic, both “black” and “white”. Demons were said to be invoked, but I am not aware of any actual _possession_ occurring resultant from such invocation – perhaps physical attack or bad luck, yes; but not literal possession calling for exorcism. Please correct me if I’m mistaken about this.
(It is also important to recall that the New Testament never portrays Jesus or his disciples as exorcising Satan or the Devil. The only entities that Jesus and his disciples exorcise are local demons, “unclean” spirits, and “spirits of disease”. Literal possession is never ascribed to Satan himself, although the sound principle did apply, that if you cast out Satan’s minions, you were in a real sense, vanquishing Satan. It is for this reason that when Jesus’ disciples returned from a mission that included exorcism, he told them, “I saw Satan fall from the sky like lightning”. The disciples had expelled Satan’s imps from possessed people, and Satan thereby suffered a major “hit”.)
However, spirit possession, as opposed to demon possession, is a widely-attested and documented phenomenon.
In many non-Christian cultures, possession is frequently looked on as a positive and necessary thing, and the possessing entities are not demons or the Christian Satan. Rather, they are ancestral spirits, shamanic/totemic spirits, or gods such as the Loa in Haitian Voudou. Tibetan Buddhism has exorcistic rituals for local demons and “elemental” spirits which differ strikingly from Christian rites, in that – because of Buddhism’s accent on universal compassion for all sentient beings – the Buddhist ritual applies “tough love” to demons, reminds them of their own innate but neglected Buddha nature, and does not usually try to punish them or drive them out violently.
I would guess that if a Buddhist, a Hindu, Sioux shaman, a Confucianist, etc., reported possession by a specifically _Christian_ demon, then the reporter must have been exposed to Christian demonology. After all, Satan, dybbuks, Beelzebul, Legion, etc., mean exactly nothing to non-Abrahamic cultures, and have very little power to frighten – or even interest – those populations. So, “Satanic possession” in non-Abrahamic cultures – even if we speculate that it does rarely occur – is most likely just one more result of Western incursion into other cultures.
Therefore it would seem that possession is a culturally-determined phenomenon. That being so, we would not expect to see Christian or Jewish demons possessing non-Jews and non-Christians. We must therefore deny our Western Devil his due. His influence is only effective for Abrahamic faiths, and does not extend into other religions.
Of course, fundamentalist Christians – who in any case are already biased toward superstition and judgmentalism – do say that the possessing entities of other cultures are “from Satan” and that the spirits and gods of non-Christian possession-cultures are really “Satan in disguise” … and the “poor natives” are too ignorant and depraved to realize it. But of course, these fundamentalists are merely projecting their own ghettoized views onto other cultures – cultures which, they falsely claim – are, even without possession, “Satanic” and Hell-bound.