Shamanism is based on the belief that the visible world is pervaded by invisible forces or spirits that affect the lives of the living. In contrast to animism and animatism, which any and usually all members of a society practice, shamanism requires specialized knowledge or abilities. Shamans are not, however, organized into full-time ritual or spiritual associations, as are priests.

The word shaman originated among the Siberian Tungus (Evenks) and literally means he (or she) who knows; the belief that it may be derived from Sanskrit may be due to a confusion of shamanism and shramanism, from sanskrit shramana, Pali and Prakrit samana; but the samanas were ascetics, not shamans.

There is a strong shamanistic influence Bon on central Asian and Tibetan Buddhism which also uses Sanskrit, so perhaps there is an overlap from popular etymology, if not a direct linguistic influence. Buddhism became popular with shamanic peoples such as the Tibetans, Mongols and Manchu after the fourteenth century. Forms of shamanistic ritual combined with Tibetan Buddhism became institutionalized as state religion under the Chinese Yuan dynasty and Qing dynasty.

Shamanistic practices are thought to predate all organized religions, and certainly was practiced in the neolithic. Aspects of it are encountered in later, organized religions, generally in their mystic and symbolic practices. Greek paganism was influenced by it, reflected in the stories of Tantalus, Prometheus, Medea, Calypso and many others, as well as in the Eleusinian Mysteries (and other mysteries). The transsubstantiation of bread and wine in the Catholic religion can be seen as a shamanic relic, suggestive of the use of entheogenic (psychedelic) substances to attain spiritual realization.