Zombie Research Society
The Songhai Tribe of West Africa 
don’t wait for zombies to rise from the grave. They create their own by inviting the dead to enter their bodies, turning them into terrifying monsters that terrorize other villagers.
ZRS Researcher, Sean McCrae, points out that this is not the same as a spiritual possession:
“The Songhai believe that their summoned zombies are entirely new creatures occupying an empty human shell. In this way, it is strikingly similar to typical depictions of zombies in film and books.”
Clearly, the Haitian Voodoo tradition is not the only example of tribal zombies. Cultures across the planet have long had an understanding of the threat the walking dead present to the survival of the human race.
But why some groups choose to invite the menace into their lives in anybody’s guess.