Santi Quattro Coronati is an ancient basilica in Rome, Italy. The church dates back to the 4th (or 5th) century, and is devoted to four anonymous saints and martyrs. The complex of the basilica with its two courtyards, the fortified Cardinal Palace with the Saint Silvester Chapel, and the monastery with its cosmatesque cloister is built in a silent and green part of Rome, between the Colosseum and San Giovanni in Laterano, in an out-of-time setting.
"Santi Quattro Coronati" means the Four Holy Crowned Ones [i.e. martyrs], and refers to the fact that the saints' names are not known, and therefore referred to with their number, and that they were martyrs, since the crown, together to the branches of palm, is an ancient symbol of martyrdom. According to the Passion of St. Sebastian, the four saints were soldiers who refused to sacrifice to Aesculapius, and therefore were killed by order of Emperor Diocletian (284-305). The bodies of the martyrs were buried in the cemetery of Santi Marcellino e Pietro, on the fourth mile of via Labicana, by Pope Miltiades and St Sebastian (whose skull is preserved in the church). Miltiades decided that the martyrs should be venerated with the names of Claudius, Nicostratus, Simpronianus and Castorius; these names — together to a fifth, Simplicius — were those of five Pannonian martyr stonemasons. These martyrs were later identified with the four martyrs from Albano, Secundus (or Severus), Severianus, Carpoforus (Carpophorus) and Victorinus (Vittorinus). The bodies of the martyrs are kept in four ancient sarcophagi in the crypt. According to a lapid dated 1123, the head of one of the four martyrs is buried in Santa Maria in Cosmedin.
Tradition holds the first church was begun by Pope Miltiades, in the 4th century on the north side of the Coelian Hill. One of the first churches of Rome, it bore the Titulus Aemilianae from the name of the foundress, who probably owned the elaborate Roman villa, whose structure is evident under the church. The church was completed the end of the 6th century, and because of its proximity to the medieval papal residence of the Lateran Palace, it became prominent in its day. The first renovations occurred under Pope Leo IV (847-855), who built the crypt under the nave, added to side aisles, enclosed the courtyard before the facade, and built the belltower and the chapels of Saints Barbara and Nicholas. The new remarkable basilica, Carolingian in style, was 95 m long and 50 m wide.