Introduction
Any encyclopedia will tell you that Epona was the Celtic goddess of horses. So will many websites; usually they just state this without citing any sources or giving further details. How do we know there was any such goddess?
A little further digging reveals the problem. There is very little written in modern times, in English, on Epona. Until recently, the best work on the subject was a difficult to get book published in 1895 and written in French. For the past four years, the authors of this site have researched the literature, visited museums, and plagued inter-library loan offices. On this website, the fruits of this research are presented to an English-speaking audience. Examining the evidence for Epona we ask: when and where was she worshipped? How, and by whom?
Evidence for Epona
The historical evidence consists of direct evidence - linguistics (discussed below), epigraphic (such as dedicatory inscriptions), and written references in literature - and indirect evidence, in the form of archaeological material such as Epona statues, the remains of temples, and so on.
The name 'Epona'
The name Epona comes from Gaulish, a member of the Celtic family of Indo-European languages. Gaulish was spoken during the later Iron Age (La Tène C and D, around 300 BCE to 50 BCE) and then in parallel with Latin during the Roman Civil War and Roman Empire (50 BCE onwards), gradually dying out over the next four centuries.
Gaulish was spoken over much of continental north-western Europe including modern France, Belgium, Holland, Switzerland, Austria, and Germany[Lambert pp13-24, Mallory]. Related Celtic languages were spoken in Spain (Celtiberian), in Britain (Brythonic, or British, from which later developed Welsh, Cornish and Breton), in northern Italy (Lepontic), Hungary and Romania (Danubian), and as far east as Turkey (Galatian) [Mallory].
The word epos means horse in Gaulish, derived from the proto-Indo-European root *ék̂u̯os and giving similar words in other Indo-European languages such as equus (Latin), ech (Old Irish), ešva (Old Lithuanian), ekvon (Venetian) and Ηιππος (híppos, Greek) [Delamarre p. 163-4], the latter giving the English name hippopotamus, water horse.
In Gaulish, -os is the masculine singular ending and –a, the female singular [Lejeune p.325, Lambert pp. 29-30]. Thus epa means a mare, a female horse.
Personal names frequently contained the word horse, for example Epacus, Epasius, Eppius, Eppia, Επηνοσ (Epenos), Epomeduos, Eporedorix as did the names of tribes, such as the Επίδιοι (Epidii) in Scotland or of places, such as Epomanduodurum in France [Delmarre pp. 163-164 and pp. 355-389 ]. Here for example is a Gaulish coin of the Meldi, from 60-50 BCE bearing the abbreviated legend ΕΠΗΝΟ (Epenos):
The component -on- is frequently found in the names of Gaulish or Gallo-Roman divinities including, besides Epona, such examples as Divona, Maponos, Carnonos, Matrona, Rigatona, Sirona [Jufer]. However, it is also found in other contexts like personal names and in the names of months (such as Giamonios) [Lambert p.108-115] and there are divine names that do not have it, such as Esus. It should probably be considered to be a way to turn the name of an object into a personal name [Gwinn]. The name Epona thus means, in Gaulish, ‘divine mare’ or 'she who is like a mare'.
Although Celtic peoples possessed writing in the late Iron Age, they did not produce a body of literature in their native languages, or use monumental dedicatory inscriptions before becoming part of the Roman Empire. Thus, the Gaulish name Epona is only found as a foreign word in Latin or Greek inscriptions or in the literature.
References
Delamarre, X. (2003). Dictionaire de la Langue Gauloise. Paris, Editions Errance.
Gwinn, C. pers. comm. 2004
Jufer, N. and T. Luginbühl (2001). Répertoire des dieux gaulois. Paris, Editions Errance.
Lambert, P.-Y. (1997). La Langue Gauloise. Paris, Editions Errance.
Lejeune, M. (1971). Lepontica. Études Celtiques
Mallory, J. P. (1991). In Search of the Indo-Europeans: languages, archaeology and myth. London, Thames and Hudson.