Why is Saint John Lateran the official cathedral of Rome?

Founded in 324, the Archbasilica of Saint John Lateran is the oldest public church in Rome and the Western world. Although St. Peter's Basilica is widely recognized for papal events, Saint John Lateran contains the papal cathedra and serves as the true cathedral of the Diocese of Rome. Located outside Vatican City proper, the archbasilica complex retains extraterritorial status belonging to the Holy See under the 1929 Lateran Treaty.

What we know

• Founded in 324, Saint John Lateran is the oldest basilica in the Western world and the oldest public church in Rome. [3]
• The Archbasilica of Saint John Lateran contains the papal cathedra, making it the official ecclesiastical seat of the pope rather than St. Peter's Basilica. [2, 3, 5]
• Under the 1929 Lateran Treaty with Italy, the archbasilica and its surrounding complex possess extraterritorial status despite being outside Vatican City. [2, 3]
• The President of the French Republic holds the ex officio title of First and Only Honorary Canon of the archbasilica. [3]

Still open

• The exact historical circumstance under which the Bishop of Rome acquired the Lateran property is unclear, as the traditional report relies partly on the forged Donation of Constantine.

Where to go next

• compared withHow does Saint John Lateran compare to St. Peter's Basilica?
• what caused itWhat role did Emperor Constantine play in Christianizing Rome?
• the bigger pictureWhat are the four major papal basilicas of Rome?
• a case in pointHow did an ancient Egyptian obelisk end up at the Lateran square?
• what followedWhat legal privileges did the 1929 Lateran Treaty grant?
• an unexpected connectionWhy does the French president hold an official role in a Roman church?The head of state of France, currently Emmanuel Macron, serves ex officio as the First and Only Honorary Canon of the archbasilica in a tradition dating back to King Henry IV.

Sources

• [1]Lateran (Wikidata Q468405) · CC0 1.0
• [2]Lateran · CC BY-SA 4.0
• [3]Archbasilica of Saint John Lateran · CC BY-SA 4.0
• [4]Lateran Obelisk · CC BY-SA 4.0
• [5]St. Peter's Basilica · CC BY-SA 4.0

Your path

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4. /Why is Saint John Lateran the official cathedral of Rome?