Julius Tischler (Peter II, 1998-?). Almost nothing is known by this claimant, apart from that he was German and aged ninety when he proclaimed himself pope in 1998, taking Peter II as his papal name.
Maurice Archieri (Peter II, 1995-2016), born 1923 was a former car mechanical, who lived in Le Perreux-sur-Marne, France. After an “intellectual vision” at Pentecost 1995, he claimed to be Vicar of Christ (in spiritualibus) in the end times. He took the name Peter II but did not claim to be the pope. The reason given by Archieri was that there could be no pope in the current era, as the Roman Church had “eclipsed” and no orthodox Roman hierarchy was left. According to Archieri the true church in the end time is L’Église Réelle Occultée, the Real Hidden Church, and not the Roman Catholic Church.
Valeriano Vestini (Valerian I, 1990-1995) was born Olinto Vestini, taking the name Valeriano when he joined the Capuchin order. He later became superior of the Mater Domini monastery in Chieti. In 1983, a local woman called Rita claimed to have dreams which featured Vestini as a representative of Padre Pio. The dreams included a divine command: that the group around her should work for the salvation of souls, joining forces with the seers of Lourdes, Fatima and Medjugorje. Rita left the group in 1989, and the role as the voice-box of heaven was taken over by Nicola Di Carlo and Alessandro Di Donato.
Aimé Baudet (Peter II or Peter Athanasius II, 1984?) is a Belgian man, who lived in Brussels. According to some reports, this man enthroned pope before St. Peter’s grave in 1984. Allegedly, he was a Palmarian ex-bishop. Still, this seems to be something of an urban legend.
Francis Konrad Maria Schuckardt (Hadrian VII 1978?/1984?-) was born in Seattle in 1937. He graduated from a Jesuit University in 1959 and briefly entered the priest seminary in Carthage, Missouri, which he had to leave due to illness. Thereafter, he worked as a high school teacher and was very active in the Blue Army of Our Lady of Fatima, eventually becoming a member of its International Council. In the mid-1960s, however, Schuckardt was dismissed from the Blue Army for publically condemning Vatican II, and he became one of the first active sedevacantists in the United States.
See updated article here:
Gino Frediani (Immanuel I, 1974-1984) was born in 1913 and served as a parish priest in Gavinana in Italian Pistoia from the 1940s onwards. Beginning in 1973, he claimed to receive apparitions from Old Testament prophets. On 5 September 1973, he asserted that the prophet Habakkuk had placed a hand on his head saying that the Italian parish priest was chosen to fulfil a great universal mission: “to build a Holy Church to the Sacred Heart of Jesus”.
The Palmarian church evolved from a series of purported apparitions at Palmar de Troya in Spanish Andalusia from 1968 onwards. One of the seers, Clemente Domínguez Gómez and his brother in arms, Manuel Alonso Corral soon began to dominate the cult. The movement led by them became institutionalized. A religious order was founded, priests were ordained a bishops consecrated. At the death of Paul VI, in 1978, Clemente Domínguez testified that Christ had crowned him pope under the name Gregory XVII. The Holy See was moved to Palmar de Troya and the Holy Catholic Apostolic Palmarian Church was founded. The first pope was thus mystically elected, but he elected his successor Manuel Alonso (Peter II), who in his turn appointed Ginés Jesús Hernández Martínez (Gregory XVIII) his successor. When Gregory XVIII left the church in 2016 he was succeeded by the Swiss Markus Joseph Odermatt (Peter III)
For a detailed study on the Palmarian church, see my 2017 book A Pope of their Own: El Palmar de Troya and the Palmarian Church [2nd edition, 2020]
Without any doubt, the Legio Maria, founded in Kenya in the early 1960s, is the largest of the churches in this overview. Although it is very difficult to estimate the numbers of followers, some researchers state around one million followers, while some give even higher estimates. During its existence, it has had at least three popes. The founder, Simeo Ondeto could be included, too, but he was also considered the Messiah, and today they are two claimants to the Legio Maria papacy.
Gaston Tremblay (Gregory XVII, 1968-2011) was born in Rimouski, Quebec 1928 into a rather poor family. His father died when he was young, and his mother became a nun. At age sixteen, Tremblay moved to Montreal to join the Brothers of St. John, the Hospitalers. There he was renamed Brother Jean and worked with terminally ill patients. Around 1947, he began to receive apparitions, and in 1949, he claimed to have seen the face of a future pope in a vision.