Spiritism is based on the five books of the Spiritist Codification written by French educator Hypolite Léon Denizard Rivail under the pseudonym Allan Kardec reporting séances in which he observed a series of phenomena that he attributed to incorporeal intelligence (spirits). His assumption of spirit communication was validated by many contemporaries, among them many scientists and philosophers who attended séances and studied the phenomena. His work was later extended by writers like Leon Denis, Arthur Conan Doyle, Camille Flammarion, Ernesto Bozzano, Chico Xavier, Divaldo Pereira Franco, Waldo Vieira, Johannes Greber and others.
Spiritism has adherents in many countries throughout the world, including Spain, United States, Canada, Japan, Germany, France, England, Argentina, Portugal and especially in South American countries such as Cuba, Jamaica, and Brazil, which have among the largest proportion and greatest number of followers.