I came across a reference yesterday to an inscription referring to a “babylonian priest of mithras”, here.: Amar Annus, The soul’s ascent and Tauroctony: On Babylonian sediment in the syncretic religious doctrines of late antiquity, Studien zu Ritual und Sozialgeschichte im Alten Orient, 2007, p.1-54. On p.31 we find this interesting statement, after noting that “Chaldean” was synonymous with astrologers in late antiquity:
In a fourth century AD Latin inscription (V 522) we even find a reference to a “Babylonian priest of Mithras” in Rome:
“High-born descendant of an ancient house, pontifex for whom the blessed Regia, with the sacred fire of Vesta, does service, augur too, worshipper of reverend Threefold Diana, Chaldean priest of the temple of Persian Mithras (Persidiq(ue) Mithrae antistes Babilonie templi), and at the same time leader of the mysteries of the mighty, holy Taurobolium” (Clauss 2001:30).
V 522 is of course Vermaseren’s CIMRM, but my copy of this has still not arrived.
A search on the Clauss-Slaby database (which, I find, has moved — link on the right updated) gives this full inscription, found in Rome (CIL 06, 00511 (p 3005) = CLE 01529)
Matri deum Magnae Idaeae et Attidi Menoturano sacrum nobilis in causis forma celsusque Sabinus hic pater Invicti mystica victor habet sermo duos reservans consimiles aufert et veneranda movet Cibeles Triodeia signa augentur meritis simbola tauroboli, Rufius Caeionius Cae(ioni?) Sabini filius, vir clarissimus, pontifex maior, hierofanta deae Hecatae, augur publicus populi Romani Quiritium, pater sacrorum Invicti Mithrae, tauroboliatus, Matris deum Magnae Idaeae et Attidis Minoturani et aram, IIII Idus Martias, Gratiano V et Merobaude consulibus dedicabit, antiqua generose domo cui regia Vesta pontifici felix sacrato militat igne, idem augur, triplicis cultor venerande Dianae, Persidicique Mithrae antistes Babyloniae templi, taurobolique simul magni dux mistice sacri.
What a very long list of cults to share a priest! In the reign of Gratian, Mithras had fallen on hard times, to be mentioned only in passing in a dedication to Cybele and Attis. The date — 4 days before the ides of March, in the 5th consulate of Gratian and Merobaudes, must be early in 380 AD.