Throughout the ages, Catholic clergy have been styled by various titles. The most common title is Reverendus. In addition to the superlative degree thereof (Reverendissimus), clerical dignitaries also were styled with various secular titles such as Dominus (Lordship), Illustrissimus, and Amplitudinis (Grandeur). Into the twentieth century, bishops continued to be addressed as Most Reverend and Illustrious Lordship, while, in the English speaking world, archbishops were addressed, in the style of dukes, Your Grace. Cardinals were and are styled Eminence after the highest officials of the Byzantine court, and the Pope is called Sanctitas (Holiness) or Beatissimus Pater (Most Blessed or Holy Father).
The title of Excellency is secular in origin and began to be given to civil officials such as ambassadors in the eighteenth century. Thus apostolic nuncios (papal ambassadors) and other dignitaries of the papal court acquired the title Excellentia with the addition of Reverendissima to distinguish it from secular excellencies. Diocesan bishops began to acquire the title with greater frequency in the nineteenth century. For example, Metropolitan Sheptytsky, who held various state offices in the Austrian Imperial system, was addressed as Excellency inside Austria but as Illustrissimus ac Reverendissimus Dominus by the Roman Curia or Amplitudo Vestra/Votre Grandeur by other clergy.
With the fall of the continental empires at the end of the First World War, noble titles lost the universal legal force they once possessed and their use began to wane somewhat in civic circles. The ambassadorial title of Excellency began to be attributed to bishops with greater frequency. The solemn concordats concluded between the Apostolic See and new European regimes had force of law in both civil and ecclesiastical spheres, and granted state recognition to the Catholic Church and its structures. Thus, following the conclusion of the 1925 concordat with Poland, the Roman Curia began to address Polish bishops with the title of Excellency as opposed to Lordship. Throughout the British Empire, however, the ducal style of Grace for archbishops and Lordship for bishops was recognized in civil law for Anglican hierarchs, the lords spiritual, each of which was a parliamentary peer of the realm. The same titles were used out of courtesy for Catholic bishops of the Empire.
Following the conclusion of the Concordat with Italy and the Lateran Treaty, the Holy See gained international legal recognition. The Pope, as spiritual and temporal sovereign, was thus able to grant an internationally recognized legal title to all Catholic bishops throughout the world. In the audience given to the Prefect of the Sacred Congregation of Ceremonial on 11 December 1930, Pope Pius XI decreed that, henceforth, the title of Excellentia Reverendissima (Most Reverend Excellency) was to be used to style both Latin and Oriental patriarchs, apostolic nuncios, archbishops and bishops, and certain dignitaries of the Roman Curia. The decree enacting this decision was issued by the Prefect, Cardinal Gennaro Granito Pignatelli di Belmonte on 31 December 1930 and was subsequently published in the Osservatore Romano issue of 24 January and on page 22 of the 1931 Acta Apostolicae Sedis.
Immediately, the problem of the Eastern Catholic Patriarchs arose. As spiritual heads of their Churches they had been styled Beatitude in order to raise them above other metropolitans and bishops. Since the mainstream Catholic theology and canon law did not yet understand the concept of Particular Churches, many Roman curialists considered the title Beatitude to be abusive, and proper only to the Roman Pontiff because it had been addressed by St. Jerome to Pope St. Damasus in 384. Such was the tenure of the previous decree of the Ceremonial Dicastery (June 1893) and was the verdict of an article in the Catholic Encyclopedia of 1913.
It appears, however, that the Vatican Congregation for the Oriental Church(es) had not been consulted on the matter. Regarding the new title of Excellency, Monsignor Amletto Cicogniani, assessor of the Oriental, sent a formal thank you to Ceremonial on 22 January 1931. Nevertheless, only two months later, the dicastery’s head, Cardinal Luigi Sincero, brought the matter to the attention of the Pope in an audience of 14 March. He explained that the Cardinals of the Ceremonial Congregation had ignored the preparatory studies for the codification of Oriental Canon Law which had recommended that patriarchs retain a title distinct from bishops. Perhaps not wanting to provoke further conflicts in the other curial departments, the Pope ordered that, henceforth, the Oriental Congregation address Eastern Catholic patriarchs as Beatitude so that “in this way, this qualification would be introduced without issuing, for the moment, a special decree.”
In January 1938, papal secretary of state Cardinal Pacelli consulted the Oriental Congregation regarding letters to be sent to the Melchite Patriarch. The drafts in question had been addressed to “His Excellency”, at which Sincero’s successor, Cardinal Eugène Tisserant, remarked: “Why withold the title Beatitude for the Melchite Patriarch? Is it someone from the Secreteriat of State?” Pacelli, upon becoming Pope Pius XII, would correct this oversight definitively for with his motu proprio Cleri Sanctitati in 1957, he finally granted the title Beatitude to Eastern Catholic patriarchs by full force of the law (canon 273, 10).