Basilica of Santa Maria in Trastevere Historical Timeline

A tavern site given to Christians by a pagan emperor, and a church on the same ground ever since.

Chronology

1. c. 220 — Pope Callixtus I founds a house-church here, on the site of the Taberna meritoria, a refuge for retired soldiers. Structural impact: a domestic building adapted for worship. What you see today: the reason the basilica stands on this spot rather than a grander one — it inherited a tavern.
2. c. 220s — the emperor Alexander Severus settles a dispute between the Christians and the tavern-keepers over the site, saying, in the words of the Liber Pontificalis, "I prefer that it should belong to those who honor God, whatever be their form of worship." Structural impact: the ground passes to Christian use. What you see today: a church that exists because a pagan emperor ruled in its favour.
3. 340 — Pope Julius I rebuilds it on a larger scale. Structural impact: from house-church to basilica. What you see today: the footprint the present nave still follows.
4. 5th and 8th centuries — two restorations. Structural impact: repairs rather than redesign. What you see today: continuity — the building was never abandoned.
5. 1140–1143 — the church is re-erected on its old foundations under Pope Innocent II. Structural impact: the basilica as it now stands, using 22 granite columns taken from the ruins of the Baths of Caracalla. What you see today: the nave, and the apse mosaic in which Innocent II holds a model of the church he paid for.
6. 1291 — Pietro Cavallini completes the Life of the Virgin mosaics below the apse vault. Structural impact: none; decoration. What you see today: the single best reason to walk to the far end.
7. 1617 — Domenichino paints the octagonal Assumption of the Virgin for the coffered ceiling he designed. Structural impact: a Baroque ceiling over a Romanesque nave. What you see today: the collision of the two, directly overhead.
8. 1702 — Carlo Fontana restores the façade, replacing the ancient porch with the present classicizing one and adding the balustrade with statues of four popes. He also restores the fountain in the piazza. Structural impact: the front of the church becomes eighteenth-century. What you see today: everything you look at from the piazza.
9. 1870 — scholars having identified faces carved on the nave capitals as Isis, Serapis and Harpocrates, a restoration under Pius IX hammers the offending faces off. Structural impact: deliberate damage to twelfth-century spolia. What you see today: the erasures, which are now the most eloquent thing about the capitals.

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