Mithraism is an ancient religion, the mysteries of which were regarded by the Romans as having Persian or Zoroastrian sources. Its primary focus is on the deity Mithra, a god of the sun. It was a notable religion in pre-modern Europe and ancient Persia, but it declined due to increasing conversion to Roman Catholicism and Islam. Several antiquarians like Agrippa, Weyer, and Alexander of Brennenburg studied Mithraism in the 16th century, in an attempt to unlock the mysterious power of the Orbs.
Mithraic artifacts, most notably the Orbs, play a major role in Amnesia's backstory. The Orbs contain great power in them, which Alexander wants to use to power the Traveller's Locket and return home.
Mithraism was a mystery religion practised from the 1st to 4th centuries. The religion entered Europe after Alexander the Great's conquests, and saw a rapid spread during the Roman Empire. After the rise of Christianity, many Mithraic temples were abandoned, leaving their great power untouched for centuries. In the early Industrial Age of Europe, several Mithraic temples called a mithraeum were discovered by archaeologists and explorers, like Daniel and Johann Weyer.
The origin of the cult of Mithra dates from the time that the Hindus and Aryans still formed one people, for the god Mithra occurs in the religion and the sacred books of both races, i.e. in the Vedas and in the Avesta.
The first principle or highest God was according to Mithraism "Infinite Time"; this was called Aion or Saeculum, Kronos or Saturnus.
- A symbol similar to the v-rod appears near the end of the game in one of the two rooms in front of the orb chamber.
- Professor Herbert was so desperate to find one of the mystic orbs that he journeyed all the way to Algeria with his research assistant Daniel to try and locate the Tomb of Tin Hanan, a mithraeum. He needn't have bothered. Nearby in the City of London is located The Temple of Mithras, in Walbrook Street. It was not discovered in real-life until the 1950s.
- Whether the god Mithra is merely a pagan myth or an actual being is uncertain, as the orbs clearly have supernatural power, guarded by an unworldly force, the Shadow. This Guardian of the Orbs' true name and appearance is not known. It is possible that the Shadow may be one of Mithra's creations, protecting his holy artifacts from humans who would wield their unnatural powers and potentially cause havoc.
- On the other hand there are many iconic scenes monuments of Mithras that show him slaughtering a bull. The giant bovine itself may also be the Shadow. Zoroastrianism interpretations of it depict him or another deity slaying the primordial creature Gavaevodata, the progenitor of all life. The original beast was killed in the creation myth, but from its marrow, organs and flesh the world is repopulated with life which may have a connection with the Shadow which is only represented by the manifesting fleshy matter it forms.
- The orbs could be representations of the sun and/or the stars.