Santi Quattro Coronati is an ancient basilica in Rome. The church dates back to the 4th (or 5th) century, and is devoted to four anonymous saints and martyrs.
“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 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 (r. 284–305). The bodies of the martyrs were buried in the cemetery of Sainti 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 stone dated 1123, the head of one of the four martyrs is buried in Santa Maria in Cosmedin.