CASTULUS, Saint. — He is commemorated in the Martyrologium Hieronymianum on January 12 and March 26. A marginal note added to the De locis sanctis martyrum states that between the Via Prenestina and the Via Casilina there existed a church of SS. Stratonicius and C., whose bodies lay beneath the ground. In the Tours collection there is a votive poem to C. The accounts of C.’s martyrdom come from the legendary Passio of St. Sebastian, whose author claims to know that C. was a cubicularius of Diocletian and sheltered Christians in his residence on the Palatine: but, betrayed by a certain Torquatus, he was cast into a pit on the Via Labicana and buried alive under a mass of sand.
The cemetery was discovered near the aqueducts in 1672, visited by Fabretti, noted by Mabillon, and especially emptied at the time of Boldetti, who declares it to have been very extensive (cf. Osservazioni sopra i cimiteri dei ss. Martiri, Rome 1720, p. 563). Many of its galleries were destroyed during the construction of the Rome–Civitavecchia railway in 1864, but De Rossi observes that they were not intact. The bombing of August 1943 brought to light some cemetery galleries along the railway embankment, but in poor condition and completely devastated.
Among the archaeological material from the cemetery, the inscription that mentions the martyr domun Castulu, the catibabicu secundu and the staircase is considered spurious; this epigraph is reproduced in all manuals. An inscription from the surface soil bears the date of the year 527; some fragments of a Christian sarcophagus were published in 1908 by Bartoli.