Lugus
Lugus is a Celtic god whose worship is attested in the epigraphic record. No depictions of the god are known. Lugus perhaps also appears in Roman sources and medieval Insular mythology.
Various dedications, concentrated in Iberia and dated to between the 1st century BCE and the 3rd century CE, attest to the worship of the god Lugus. However, these predominately describe the god in the plural, as the Lugoves. The nature of these deities, and their relationship to Lugus, has been much debated. Only one, early inscription from Peñalba de Villastar, Spain is widely agreed to attest to Lugus as a singular entity. The god Lugus has also been cited in the etymologies of several Celtic personal and place-names incorporating the element "Lug-".
Julius Caesar's description in his Commentaries on the Gallic War of an important pre-Roman Gaulish god has been interpreted as a reference to the god Lugus. Caesar's description of Gaulish Mercury has been examined against Insular sources, as well as the prominence of "Lug-" elements in Gaulish place-names. A prominent cult to Mercury in Roman Gaul may provide more evidence for this identification.
Lugus has also been connected with two figures from medieval Insular mythology. In Irish mythology, Lugh is an important and supernatural figure. His description as a skilled artisan and founder of a harvest festival has been compared with Gaulish Mercury. In Welsh mythology, Lleu Llaw Gyffes, a protagonist of the Fourth Branch of the Mabinogi, is a more minor figure, but is linked etymologically with Irish Lugh. He perhaps shares with the Lugoves an association with shoemaking.
The reconstruction of a pan-Celtic god Lugus from these details, first proposed in the 19th century by Henri d'Arbois de Jubainville, has proven controversial. Criticism of this theory by scholars such as Bernhard Maier has caused aspects to be abandoned, however scholars still defend the reconstruction.
Etymology
The etymology of Lugus's name has been the subject of repeated conjecture, but no single etymology has gained wide acceptance.The most commonly repeated etymology derives the name from proto-Indo-European *. This etymology is closely tied to proposals to identify Lugus as a solar god. However, Garrett Olmsted has pointed out that this derivation poses phonological difficulties. Proto-Celtic lug- cannot develop from proto-Indo-European leuk-, according to the known sound changes between the two languages. has noted that this root would result in Irish Luch, rather than the attested Irish Lugh.
and Erich Hamp have proposed that the name derives from a proto-Celtic word meaning "oath". John T. Koch has taken this hypothesis up, and proposed that the early Irish oath tongu do dia toinges mo thúath is a suppressed oath to Lugus. A. G. van Hamel and Maier proposed a derivation from proto-Celtic lugus, perhaps used allusively to mean "warrior", but an article by John Carey found the evidence for the existence of such a word in proto-Celtic lacking. Other etymologies derive "Lugus" from the name of the Norse god Loki, proto-Celtic luc-, and supposed Gaulish lougos.
Linguistic evidence
Epigraphy
A number of dedications to Lugus, dating between the 1st century BCE and 3rd century CE, have been found in Continental Europe. This epigraphic data is concentrated in Iberia; only a small number of inscriptions are known from Gaul, and none are known from Britain or Ireland. A peculiarity of this data is that the singular of Lugus's name is rarely recorded. There is consensus that a Celtiberian inscription from Peñalba de Villastar features the singular. A minority interpret the Gaulish-language Chamalières tablet as invoking singular Lugus. The singular is inscribed on a ceramic sherd from, but this is probably a theophoric name and not a reference to the god Lugus. Many Celtic gods are referenced both in the plural and the singular, but in dedications to Lugus the plural form predominates.The nature of the Lugoves, and their relationship to Lugus, has been much debated. The epigraphic record is equivocal as to the gender of these deities. The epithet Arquienob has masculine gender, whereas the epithets Arousa and possibly Niirabo indicate the feminine. Henri Gaidoz contended that plural deities were minor in the Celtic pantheon, and that therefore Lugus could not have been the chief god of the Celts. Arbois de Jubainville and Joseph Vendryes argued that the Celts invoked even major gods in the plural. Some scholars have tried to explain the multiplicity of the Lugoves through traits of Irish Lugh or Welsh Lleu. Marie-Louise Sjoestedt, for example, pointed out that Lugh was one of triplets. Maier has argued that the obscurity of the nature of the Lugoves limits the value of the epigraphic record as evidence for pan-Celtic Lugus. Krista Ovist argues against this point.
Proper names
The element "lug-" appears frequently in Celtic proper names. In many of these cases, an etymology involving the deity-name Lugus has been proposed. Celtic personal names with this element include Lug, Lugaunus, Lugugenicus, Lugotorix, Luguadicos, Luguselva, and Lougous. A number of cognate names are known from Irish Ogham inscriptions, for example, Luga, Lugudecca, Luguqritt, and Luguvvecca. Some ethnic names have been connected with Lugus, for example the Lugi in Scotland and the in Asturias. Place-names connected with Lugus include Lugii, Lougoi, Lougionon, Lugisonis, and Lugnesses. Lucus Augusti is the site of a Roman sanctuary with dedications to the Lugoves; its name may be derived from the deity-name Lugus, though it could simply be Latin for "grove of Augustus". The name of Luguvalium is sometimes glossed as "wall of Lugus", but may instead derive from a personal name.File:France map Lambert-93 topographic-ancient Roman roads.svg|thumb|Lugdunum at the heart of Roman Gaul
Since Arbois de Jubainville argued for the connection, the place-name "Lugdunum" has frequently been connected etymologically with Lugus. The most famous known by this name is Lugdunum in the region of Gallia Lugdunensis, a Roman colony and among the most important cities of Roman Gaul. The etymology of this place-name has been the subject of much conjecture. Following Arbois de Jubainville, the most widely held hypothesis analyses the name as Lugus + dunum, that is, "the fortress of Lugus". Many other etymologies have been given. An ancient etymology derives it from a Gaulish word for raven. Attempts have been made to analyse it as *lugus + dunum, bolstered by a medieval etymology which gives the gloss mons lucidus.
The place-name Lugdunum is attested, in its cognate forms, as the name of as many as twenty-seven locations. Apart from Lyon, there is Lugdunum Convenarum, Lugdunum Batavorum, Lugdunum Remorum, two Welsh places named Din Lleu, and two cities of unclear location in North East England and Germania Magna. The wide range and abundance of these place-names has been used to argue for the importance of Lugus. Whatever the etymology, not all of these place-names must owe themselves a Celtic root. Lugdunum/Lyon was a major city, and other locations may have borrowed the name. Some two-thirds of the cognate place-names are attested only from the 10th century on; we know that Lugdunum Remorum had an older, native name which was displaced in the 6th century.
Caesar and Gaulish Mercury
Commentaries on the Gallic War is Julius Caesar's first-hand account of the Gallic Wars. In giving an account of the customs of the Gauls, Caesar wrote the following:Caesar here employs the device of interpretatio romana, in which foreign gods are equated with those of the Roman pantheon. With very few exceptions, Roman writings about Celtic and Germanic religion employ interpretatio romana, but the equations they made varied from writer to writer. This makes identifying the native gods behind the Roman names very difficult. Indeed, if their information was confused or their intention was propagandistic, reconstruction of native religion is next to impossible.
Caesar contrasts Gaulish Mercury with the other gods of the Gauls, insofar as he is the god about whom they do not have "much the same ideas" as the Romans. The Romans associated Mercury with trading and travel, but they did not think of him as "inventor of all arts". Another difference is suggested by the order in which the gods are presented: Mercury is given primacy, whereas the Romans considered Jupiter the most important deity. Moreover, Mercury's role as guide of souls to the underworld goes unmentioned in this passage. Caesar elsewhere ascribes to the Gauls a belief in metempsychosis, which may have precluded Gaulish Mercury from this function.
The first Celtic god to be identified as Caesar's Gaulish Mercury was Teutates. This identification was widely accepted until the late 19th century, when Arbois de Jubainville proposed that Lugus lay behind Caesar's description. Arbois de Jubainville pointed to the prominence of "Lug-" elements in Gaulish place-names, and a possible festival of Lugus at Lugdunum/Lyon. He also drew comparison between Irish Lugh's epithet Samildánach and Caesar's description of Gaulish Mercury as "inventor of all arts". Maier has criticised this identification on the basis that "inventor of all arts", though not a Greco-Roman belief about the god Mercury, is a common literary topos in Roman descriptions of foreign religions. He also casts doubt on the possibility that an epithet like this, not otherwise attested in the epigraphic record, could have survived into medieval Irish literature.
A confusing aspect of Caesar's description of this cult is his reference to the "many images" of Gaulish Mercury; specifically he uses the word simulacra, a word which had the connotation of worshipped idols for Roman authors. Archaeological evidence of anthropomorphic cult images is scant before the Roman conquest of Gaul. The testimony of some Roman authors suggests the Gauls did not produce images of their gods, though Lucan describes the Gauls as having wooden idols. Salomon Reinach suggested that Caesar meant to draw a comparison between aniconic monuments to Gaulish Mercury and the herms he knew from Rome, but this is an unlikely use of the word simulacra.
File:Moccus inscription, CIL XIII, 05676.png|thumb|Inscription from Langres deo Moccus
Certainly, after Caesar's conquest of Gaul, depiction and worship of Mercury was widespread. More images of Mercury have been found in Roman Gaul than those of any other God, but these representations of Mercury are conventional, and show no discernible Celtic influence. Epigraphic material does reveal some bynames of Mercury peculiar to Gaul, thought to be suggestive of native gods. An inscription from Langres attests to a Mercur Mocco, perhaps Lugus. Other epithets—connecting Mercury with heights, particular Gaulish tribes, and the emperor Augustus—have been thought to be suggestive of Lugus. The epigraphic record has not produced any epithets portraying Mercury as inventor or master of arts.