In his pioneering study of Yoruba theatre, Joel Adedeji traced its origins to the masquerade of the Egungun (the "cult of the ancestor"). The traditional rite is controlled exclusively by men and culminates in a masquerade in which ancestors return to the world of the living to visit their descendants. In addition to its origin in ritual, Yoruba theatre can be "traced to the 'theatrogenic' nature of a number of the deities in the Yoruba pantheon, such as Obatala the orisha of creation, Ogun the orisha of creativeness and Sango the orisha of lightning", whose worship is imbricated "with drama and theatre and their symbolic and psychological uses."