Summary — Following previous research on the origin of the Western Patriarch, the author examines the debates of Vatican I. In some inter­ventions, made with the aim of claiming the rights and privileges of the Patriarchs in comparison with the primacy, one encounters some hint, more or less direct, to the patriarchate of the West. But from the reactions to such interventions, it follows that the patriarchal institution was considered rather as a purely disciplinary reality, a characteristic and exclusive prerogative of the Eastern ecclesiastical organisation. The Bishop of Rome is not, then, to be considered as the Patriarch of the West, but Shepherd of the Universal Church, who grants to the oriental patriarchs special rights and privileges, thus making them participants of his supreme authority.