(Collecta: S. Stefano Rotondo al Celio)
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From the Churches of Rome wiki:
Santi Quattro Coronati is dedicated to a group of 4th century Roman martyrs.
According to tradition, the first church was built in the 4th century by Pope St Miltiades (311-314). It has been identified with one of the first parish churches in Rome, the titulus Aemilianae, named after the foundress. Some researchers place the foundation in the 5th century. It was restored by Pope Honorius I (625-638) and Pope Hadrian I (772-795). Pope St Leo IV (847-855) had it rebuilt as a basilica.
The church was destroyed in the Norman sack of Rome in 1084, and it found its present form - somewhat smaller than the original church - under Pope Paschal II (1099-1118). The new church was consecrated on 20 January 1116.
From the 12th to the 16th century, the church belonged to the Benedictines. A monastery and cloister were added in the 12th and 13th centuries.
In 1246, it was transformed by Pope Innocent IV so that it could function as a fortress, and was used by popes who felt unsafe in the Lateran because of the ongoing conflict with the Hohenstaufen emperors.
In 1521 it was passed on to the Camaldolese, and in 1561 it was given to the Augustinians, who still serve it.
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As a result of the 1246 rebuilding, the church looks almost like a fortress, towering above the street. It's approached through two courtyards. You also pass through the Romanesque campanile.
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Columns imbedded in the wall are from the 9th century church, where the walls opened into side aisles. With the rebuilding of the 12th century, the church got three naves instead of just one.
On the right side is the matronea, a gallery for women in Eastern style.
There's a cosmatesque floor and a coffered ceiling. The apse has frescoes from the early 17th century by Giovanni di San Giovanni. The motif is the glory of the saints.
The martyrs' relics were moved here during the 9th century rebuilding, and are preserved in ancient sarcophagi in the crypt.
