Memmius Placidus

Memmius Placidus is known from a single votive altar discovered at Caere, modern Cerveteri, generally dated to the late second or early third century CE (Antolini 2017; Chalupa 2023). The inscription records that he dedicated the monument to Mithras after being initiated as a Heliodromus by the Pater Curtius Iuvenalis:

Deo Soli Invicto Mithrae Memmius Placidus Heliodromus sacratus a Curtio Iuvenale Patre votum solvit libens merito.

Nothing else is known about his life. The inscription is nevertheless of particular importance because it provides the earliest known epigraphic attestation of the grade Heliodromus associated with a named individual (Chalupa 2023). It also preserves the formula sacratus a Curtio Iuvenale Patre, explicitly identifying the Pater who performed the initiation.

The altar, carved from a single block of fossiliferous sandstone, preserves a rectangular niche comparable to those found on other Mithraic altars, generally interpreted as spaces intended to hold lamps (Antolini 2017). Referring to this monument, Campos Méndez has suggested that this feature may also have reinforced the solar symbolism associated with the grade of Heliodromus, although he presents this as a possible interpretation rather than an established fact (Campos Méndez 2026, 144).

The dedicant’s nomen is only partially preserved. Although several restorations have been proposed, including Mammius, Memmius, Mummius, Nummius and Remmius, Antolini considers Memmius the most plausible reading because the gens Memmia is documented in the territory of Caere from the late Republican period onwards. He also notes that the inscription leaves no room for a praenomen, an omission mirrored by Curtius Iuvenalis, who is likewise identified only by his nomen and cognomen (Antolini 2017).