Ancient Papal Palace Established by Constantine Believed Found in Rome

inside a papal palacePhoto byGabriella Clare MarinoonUnsplash

In late July, news emerged regarding the ongoing excavations at the former center of the Catholic Papacy—the Patriarchio, a palace of papal authority dating back to the late Roman Empire. The structure likely never would have been discovered had it not been for roadwork being done in the plaza in front of the Archbasilica of St. John Lateran. Researchers believe that a series of walls represent defense works that protected the Patriarchio directly in the middle of the Eternal City.

Completed in 313 and known as the Lateran Palace, the site served as the seat of the papacy following Emperor Constantine’s Edict of Milan, which promoted religious tolerance of Christianity across the Empire. The complex of religious and administrative buildings gradually expanded outward until a brief period when the papacy moved to Avignon in France.

Gennaro Sangiuliano, the Italian Minister of Culture, explained:

This is an extraordinarily important find for the city of Rome and its medieval history, as no extensive archaeological excavations have ever been carried out in the square in modern times. Every single stone speaks to us and tells its story: thanks to these important discoveries, archaeologists will be able to learn more about our past.

In 2025, Rome will host a year-long pilgrimage event known as the Jubilee, expecting 30 million visitors. The excavations in the plaza in front of St. John Lateran were part of major renovations for the event. By the time the papacy returned to Rome, the Lateran Palace had fallen into disrepair and had suffered from fires and earthquakes. Defensive walls were ordered to be knocked down, and Pope Gregory XI moved the site of the palace to the Vatican, where it remains today.

In the 16th century, Pope Sixtus VI arranged for the palace to be restored, and today it blends seamlessly into the historic Roman cityscape. Three monuments survived and were incorporated into the building constructed by Domenico Fontana in 1589 opposite St. John Lateran. These monuments are the Scala Santa and the Chapel of the Sancta Sanctorum.