Thehorns of Ammon were curling ram horns, used as a symbol of theEgyptian deityAmmon (also spelled Amun or Amon). Because of the visual similarity, they were also associated with the fossils shells of ancient snails andcephalopods, the latter now known asammonite because of that historical connection.[1]
Ammon, eventuallyAmon-Ra, was a deity in theEgyptian pantheon whose popularity grew over the years, until growing into a monotheistic religion in a way similar to the proposal that theJudeo-Christian-Islamic deity evolved out of theAncient Semitic pantheon.[2] Egyptian pharaohs came to follow this religion for a while,Amenhotep andTutankhamun taking their names from their deity. This trend caught on, with other Egyptian gods also sometimes being described as aspects of Amun.[3]
Ammon was often depicted with ram's horns, so that as this deity became a symbol of supremacy, kings and emperors came to be depicted with Horns of Ammon on the sides of their head in profile, as well as the deities not only of Egypt, but other areas, so that Jupiter was sometimes depicted as "Jupiter Ammon", replete with Horns of Ammon, after Rome conquered Egypt, as was the Greek supreme deityZeus. Alexander the Great's deification as a conqueror had involved being declared the metaphorical "Son of Ammon" by the Oracle atSiwa. This tradition is thought by some to have continued for centuries, withAlexander the Great being allegedly referred to in theQuran as “Dhu al-Qarnayn” (The Two-Horned One), a supposed reference tohis depiction on Middle Eastern coins and statuary as having horns,[4][5] consistent with the view of most scholars on Islamic exegesis that Dhu al-Qarnayn was Alexander the Great.[6][7]
Pliny the Elder was among the earliest writers known to have associated spiral shells with the deity Ammon, referring to them asammonis cornua (horns of Ammon) in his bookNaturalis Historia.[8] Considering the relative rarity of ammonite fossils in Egypt, this may have originated with fossil snail shells likenatica hybrida found inMokattam limestone nearCairo.[1]
The direct attribution of the Horns of Ammon with fossil cephalopod shells became common duringMedieval times with mentions by writers likeGeorgius Agricola andConrad Gesner. These led to a widespread association that climaxed with paleontologistKarl Alfred von Zittel naming the class of animalsAmmonoidea in 1848.