Clemente Domínguez y Gómez

Antipope Gregory XVII (Latin: Gregorius PP. XVII; Spanish: Gregorio XVII; born Clemente Domínguez y Gómez; 23 May 1946 – 21 March 2005), also known by the religious name Fernando María de la Santa Faz, was the first Pope of the Palmarian Catholic Church, who in this capacity, claimed to be the 263rd Pope of the Catholic Church from 6 August 1978 until his death on 21 March 2005. He was an alleged visionary, seer and mystic, who, following claimed apparitions of the Blessed Virgin Mary as Our Crowned Mother of Palmar, founded a religious order which claimed to continue the work of the Carmelites, known as the Carmelites of the Holy Face; after 1978, this order became synonymous with the Palmarian Church.

Domínguez and several other members of the Carmelites of the Holy Face, was ordained as a priest and then consecrated as a Bishop in January 1976, by the schismatic Archbishop Ngô Đình Thục, a Vietnamese cleric of the Roman Catholic Church. This Archbishop returned to union with the church in his later years. Following the death of Pope Paul VI in August 1978, Clemente claimed to have a vision where he was allegedly mystically crowned Pope of the Palmarian Christian Church by Jesus Christ himself. He claimed that the Holy See of the Catholic Church had been moved from Rome to El Palmar de Troya, due to the supposed apostasy of the former. During his pontificate, he issued many documents between 1978 and 1980, which laid out the direction of the Church; he invalidated the Second Vatican Council and is also claimed to excommunicated the leaders of the Vatican City, declaring them Antipopes.

In close collaboration with his trusted éminence grise and Palmarian Secretary of State, Fr. Isidore (Manuel Alonso Corral), during his tenure as Palmarian Pontiff there took place two ecumenical councils; the First Palmarian Council (1980–1992) and the Second Palmarian Council (1995–2002). The result of the latter Council was a claimed divinely-mandated purification of the text of the Vulgate (the Bible preferred for many centuries by the Catholic Church), in the form of The Sacred History or Holy Palmarian Bible. His reign also oversaw the construction of the large Cathedral-Basilica of Our Crowned Mother of Palmar at El Palmar de Troya, just outside Seville in Andalusia, Spain. Following his death in 2005, the day after, Antipope Peter II (Manuel Alonso Corral), his successor, canonised him as a Catholic saint in the Palmarian Catholic Church as "Pope St. Gregory XVII the Very Great".