As explained by the Vaticanist Andrea Gagliarducci en ACI PressItalian agency of EWTN News, Benedict XVI’s decision was based on the fact that “from a historical point of view, the ancient Patriarchates of the East were relative to a fairly clearly circumscribed territory, while the territory of the Bishop of Rome remained vague”.
“However, he was included as Patriarch of the West in the imperial ecclesiastical system of Justinian, between 527 and 565. For its part, Rome favored the idea of the three Petrine episcopal sees of Rome, Alexandria and Antioch, and the Pope figured as the first of the five patriarchs at the IV Council of Constantinople (869-70), also at the IV Lateran Council (1215) and at the Council of Florence (1439).”
Gagliarducci also specifies that “the title of Patriarch of the West, used by Pope Theodore in the year 642, flourished in the 16th and 17th centuries, and the Pontifical Yearbook first described the Pontiff as Patriarch of the West in 1863.”
Currently, the historical titles of the Holy Father also include the following: “Vicar of Jesus Christ, Successor of the Prince of the Apostles, Pontiff Maximus of the Universal Church, Primate of Italy, Archbishop and Metropolitan of the Province of Rome, Sovereign of the State of Vatican City and Servant of the Servants of God.”