We will shortly go onto examine the incidence of Lleu/Lug(h) in the medieval vernacular traditions, but before we do so it may be worth considering the appearance of his Gallo-Roman incarnation - at which time he was known by the name of Lugus. We have already touched on the possible Indo-European roots of this particular figure and his associated traditions. Now it remains to be seen how these roots flourished in Late Iron Age Celtic-speaking world encountered by Caesar in the first century BC. This was the world of the proto-urban oppida, of Cassivellaunus and the coin-using Belgic dynasties of Southern England. It was also the world of the druidic priesthood, whose chief sacred centre was now located (it would seem) on the Island of Anglesey - a narrow stretch of water away from where the Mabinogi would later be composed, and the events of the Fourth Branch were intimately located. Therefore, for a number of reasons, we need to examine this Gaulish Lugus: evidently one of the most important godforms of the druidic religious system, as well as the originator of certain key motifs within the medieval tradition of the Fourth Branch.
Describing the religious habits of the Gallic Celts Caesar noted that ‘of all the gods they most worship Mercury. He has the largest number of images, and they regard him as the inventor of all the arts, as their guide on the roads and in travel, and as chiefly influential in making money and in trade’. Here, once again, we are faced with the familiar problem of the Interpreta Romana - and the extent to which the blunt observations of a Roman general can really tell us about the subtleties of Gallo-Brittonic native religious thought. However, there are some remarkable correspondences with the native tradition of Lleu/Lug, even within this brief assignation.
Like Caesar’s Mercury, the Irish Lug was considered responsible for introducing a number of arts, crafts and social institutions. Lebor Gabala credits him with being the first to bring ‘chess-play and ball-play and horse-racing and assembling into Ireland’. Cath Maige Tuired likewise describes him as samildanach ‘multi-talented’: and attributes to him the skills of a wright, a smith, a champion, a harper, a hero, a poet and historian, a sorceror, a leech and cupbearer. It is also interesting to note that Lug’s avatar and spiritual son, Cú Chulainn, is given the birth-name Sétanta, the literal meaning of which is ‘The Finder of Paths’.
In the Gaulish iconographic tradition, the figure of Mercury is represented in convention classical terms - as a semi-naked youth, wearing winged shoes and carrying the distinctive caduceus (a rod with two serpents intertwined). Other features traditionally associated with the classical Mercury, such as the cockerel and the bag of coins, are also frequently represented. In other words, there is little sign of much native input to the visual conception of the Gaulish Mercury, which specifically suggests a connection with the native figure Lugus.
In general terms, however, it is possible to see how the Ancient observers might have made this equation. Like Mercury, Lleu/Lug was consistently represented as a youthful figure in the Medieval Celtic tradition - and there is no reason to think this was not part of his original, pre-Christian conception. As the Icelandic tradition of Loki would suggest, there seems to have been a ‘trickster’ aspect to this figure at some stage in his development (though these characteristic may have transferred themselves from the Shaman/Wind God, with whom he seems to have been closely allied). The winged shoes, the winged-helmet, serpent rod and bag of coins are all tokens of various aspects of skill, speed and expertise - which are also characteristics of the Medieval Celtic figures involved. Most revealing perhaps, is the name of the goddess with whom the Gaulish Mercury is sometimes paired - Rosmerta whose floral associations recall the name of Bloddeuwedd ‘Flower Face’, the consort of Lleu in the final section of the Fourth Branch. Although no specific reference is made to Lugus Mercurius or any such compounded Gallo-Roman theonym, the accumulated weight of evidence, both from the writings of Classical observers and the iconography of Gaul before and during the Roman occupation, would suggest that a reasonably strong association existed between these two figures, and what applied to one might well have effected the conception of the other.
It is also worth briefly considering the relevant epigraphic and toponymic material. This body of evidence is of partricular interest, because it is the only category of native Gallo-Roman evidence where the god Lugus is specifically named. It is in conjunction with the numerous iconographic representations of Mercury and the observations of Caesar, that we are able to conclude from this material that Lugus would seem to have been a pre-eminent diety throughout the Ancient Celtic world.
As Rachel Bromwich points out, Lugu-/Lugus- is attested as a place-name element through a wide area of Western Europe: Lyons, Laon and Leidun all being derived from the old Celtic form Lugudunum ‘Fort of Lugus’ (cf. Welsh Dinlleu). In Britain, the old name for Carlisle, Luguvalium has been interpreted as ‘Place of Luguvalos’, Lugusvalos being a personal name evidently meaning ‘Lugus-Strong’ i.e. ‘One who is strong like (the god) Lugus’. Other personal names attested with the Lugu-/Lugus element include the Gaulish Lugudiacus and Luguselva (‘Lugus-Devoted’).
Further evidence is to be found in some scant but suggestive epigraphic evidence from the Gallo-Brittonic world. Recently, an inscribed lead plate was found near the Chalamiers region of Southwestern France. Our understanding of the Gaulish language is still in its earliest stage, so it is not possible to provide a translation. An idea of the opaque nature of this ancient inscription can be seen in this transliteration below:
Beyond the fact that this unbroken text is in the Gaulish language, exhibits metrical features, and was almost certainly the expression of a magical intention, there is little else that can be said about this enigmatic epigram. It has been variously described as invocation to bring about or bind some kind of agreement, or a curse, or an evocation of strength and vigour prior to some kind of conflict. What we do know is that the Celtic deity Maponus (see p.###) is invoked in the opening lines, and that the spell is being inscribed on behalf of a group of men with Gallo-Roman names (C. Lucios, Claudios, Marcios et al.). It is the closing formula, repeated three times, that interests us in the present context. If the interpretation of Schmidt (1982) is correct then luge dessummiíis should be read as ‘I prepare them for Lugus’, which is usually taken to refer to the invoker’s enemies. If this interpretation can be accepted, then it would suggest a martial function for the god Lugus, who (like the Germanic Oðinn) was being offered the spirits of the slain, in exchange for victory in war.
We are on rather more certain ground with the abbreviated Latin inscription, in the Spanish town of Osma ( < Clt. Uxama ‘The Highest Place’ cf. Welsh uchaf).
This has been read by W. J. Gruffydd as Lugovibus sacrum L.L. Urico collegio sutorum d[ono] d, ‘L. L. Urico donated this, sacred to the Lugoves, to the guild of shoemakers’. This is interesting for two main reasons. First, it establishes a link between Lugus/Lleu and shoemaking: a theme which is borne out in the medieval tradition, as we shall see below. Secondly, Lugovibus is a dative plural form - suggesting that Lugus, or rather ‘the Luguses’ were conceived as multiple in form in the Gallo-Roman world. It has been variously suggested that Lugus may have been a triple diety, similar to the Matres or ‘The Mothers’ attested elsewhere in the Gallo-Roman religious system. Another suggestion is that they may have been a pair of twins, like Lleu and Dylan of the Mabinogi, or even a father son/uncle-nephew pair like Gwydion and Lleu. Gruffydd makes an inspired connection with the medieval twin-saints ‘Crispin and Crispian’, patrons of shoemakers, whom he believers may express a (Christianised) reflex of these Gallo-Roman gods. Gruffydd also draws attention to the British St. Hugh, patron of shoemakers, who, with his wife Winfred was compared to the ‘two bright stars, Castor and Pollux’. The extent to which this medieval hagiography can be linked to the mythology of the pagan ‘Luguves’ remains an open question; but the inscriptions at Osma, alongside the hint within the Chamalieres fragment, prove beyond doubt that Lugus was invoked for magical purposes in the Ancient Celtic world, and seems to have had particular connection with the craft of shoemaking.
The content of this page is taken from Chapter 5 of my work on the The Four Branches of the Mabinogi (2005), which contains further discussion of Lleu/Lugus, in both his ancient and medieval manifestations. The section on the birth of Lugh is available online, and offers some thoughts on the generic 'birth of the hero' myth, and a discussion of an extraordinary appearance of Lugh as a divine avatar in the medieval Irish Tain Bó Cuailnge.