Ferrette was born in Épinal, France,[3] possibly of Protestant parents.
He thereafter studied philosophy and theology at Grenoble and Paris, and was ordained a priest on 2 June 1855.
[5]: 33 He was a Dominican missionary in Mesopotamia and Kurdistan from September to June 1856, but then apostasized from the Catholic Church.
[5]: 34 Ferrette claims he was consecrated as the Bishop of Iona and its dependencies by Mutran Boutros (later the Syriac Orthodox Patriarch of Antioch) at Homs (Emesa) on 2 June 1866 who was allegedly acting solus and would have given Ferrette a mission to introduce Oriental Orthodoxy to the West.
[5]: 35, 37 Allegedly, in Oxfordshire in 1858, Richard Williams Morgan, an Anglican priest, was conditionally "baptised, confirmed, ordained and consecrated" Patriarch of the Ancient British Church by Ferrette, and given by Ferrette the following name and full title: Mar Pelagius I, Hierarch of Caerleon-on-Usk.