Reverse: AETERNITAS S C, Pietas standing left by altar.
Pietas is a Goddess of duty, loyalty and piety.
The Imperial cult of ancient Rome identified emperors and some members of their families with the divinely sanctioned authority (auctoritas) of the Roman State. Its framework was based on Roman and Greek precedents, and was formulated during the early Principate of Augustus.A deceased emperor held worthy of the honor could be voted a state divinity (divus, plural divi) by the Senate and elevated as such in an act of apotheosis. The granting of apotheosis served religious, political and moral judgment on Imperial rulers and allowed living Emperors to associate themselves with a well-regarded lineage of Imperial divi from which unpopular or unworthy predecessors were excluded.