Rastafari, sometimes called Rastafarianism, is a religion that developed in Jamaica during the 1930s. It is classified as both a new religious movement and a social movement by scholars of religion. There is no central authority in control of the movement and much diversity exists among practitioners, who are known as Rastafari, Rastafarians, or Rastas. Rastafari beliefs are based on a specific interpretation of the Bible. Central to the religion is a monotheistic belief in a single God, referred to as Jah, who is deemed to partially reside within each individual. Rastas accord key importance to Haile Selassie, the emperor of Ethiopia between 1930 and 1974; many regard him as the Second Coming of Jesus and Jah incarnate, while others see him as a human prophet who fully recognised Jah's presence in every individual. Rastafari is Afrocentric and focuses attention on the African diaspora, which it believes is oppressed within Western society, or "Babylon". Many Rastas call for this diaspora's resettlement in Africa, a continent they consider the Promised Land, or "Zion". Some practitioners extend these views into black supremacism. Rastas refer to their practices as "livity". Communal meetings are known as "groundations", and are typified by music, chanting, discussions, and the smoking of cannabis, the latter regarded as a sacrament with beneficial properties. Rastas emphasise what they regard as living "naturally", adhering to ital dietary requirements, wearing their hair in dreadlocks, and following patriarchal gender roles. Rastafari originated among impoverished and socially disenfranchised Afro-Jamaican communities in 1930s Jamaica. Its Afrocentric ideology was largely a reaction against Jamaica's then-dominant British colonial culture. It was influenced by both Ethiopianism and the Back-to-Africa movement promoted by black nationalist figures such as Marcus Garvey. The religion developed after several Protestant Christian clergymen, most notably Leonard Howell, proclaimed that Haile Selassie's crowning as Emperor of Ethiopia in 1930 fulfilled a Biblical prophecy.