A correspondent drew my attention to this interesting statement in a current handbook. He also added some glosses (in square brackets) to make it generally comprehensible:
Cumont’s [late-19th- and early-20th-century] reconstruction suffered a mortal blow at the first conference of Mithraic studies, held in Manchester in 1971 (GORDON, 1975), and has not been revived since. The past twenty-five years have instead given rise to many—mutually exclusive—theories on the origin and nature of the Mithraic mysteries, which virtually all share a stress on the absence of [clear] links between [Iranian] Zoroastrianism and [largely post-Christian Greco-Roman] Mithraism..
That seems to hit the nail on the head.
The Dictionary of Deities and Demons in the Bible is not a handbook that I have encountered before. But the material on Mithra/Mithras — present in this volume because of the names Mithredath (Ezra 1:8) and Mithradates (1 Esdras 2:12) — seems interesting. It is a digest of secondary literature, naturally enough, and I found that it was particularly useful for Mitra, the Persian deity, and nicely drew together the various seemingly contradictory elements that make up the aspects of this god.
- H. J. W. Drijvers & A. F. de Jong, “Mithras,” Dictionary of deities and demons in the Bible (Eerdmans/Brill, 1999), p. 579↩