Cao Đài (Vietnamese: Cao Đài (help·info)) is a relatively new, syncretist, monotheistic religion, officially established in the city of Tây Ninh, southern Vietnam, in 1926. Đạo Cao Đài is the religion's shortened name, the full name is Đại Đạo Tam Kỳ Phổ Độ (Great Religion [of The] Third Period [of] Revelation [and] Salvation). The term Cao Đài literally means "Kingdom of Heaven." Figuratively, it means that highest place where God reigns. Caodaiists often use the term Đức Cao Đài (Venerable Cao Dai) as the abbreviated name for God, the creator of the universe, whose full title is Cao Đài Tiên Ông Đại Bồ Tát Ma-ha-tát (translation: Cao Dai [the] Ancient Sage [and] Great Bodhisattva Mahasattva). According to Caodaiists, the full title was purposefully chosen by God because within it are representations of the Three Teachings: Saint, Sage and Buddha.
Caodaiists credit God as the religion's founder. They believe the teachings, symbolism and organization were communicated directly from God. Even the construction of the Tây Ninh Holy See is claimed to have had divine guidance. Cao Đài's first disciples, Ngô Văn Chiêu, Cao Quỳnh Cư, Phạm Công Tắc and Cao Hoài Sang, claimed to have received direct communications from God, who gave them explicit instructions for establishing a new religion that would commence the Third Era of Religious Amnesty.
Adherents engage in ethical practices such as prayer, veneration of ancestors, nonviolence, and vegetarianism with the minimum goal of rejoining God the Father in Heaven and the ultimate goal of freedom from the cycle of birth and death. Estimates of the number of Cao Đài adherents in Vietnam vary, but most sources give 2 to 3 million. Some estimates are as high as 8 million adherents in Vietnam. An additional 30,000 (numbers may vary), primarily ethnic Vietnamese, live in the United States, Europe, and Australia.