Lugus or Lugos was a deity worshipped in Gaul, Britain, Ireland and other Celtic regions. No inscriptions have survived bearing his name (although dedications to the Lugoves, a plural form, have been found in Switzerland and Spain), but his existence can be deduced from ancient placenames and from figures in later Celtic mythology, such as the Irish Lug and Welsh Llew Llaw Gyffes.

His name was commemorated in numerous place-names, such as Lugdunum (Celtic *Lugdunon or *Lugudunon, "fort of Lugus"; modern Lyon, France), capital of the Roman province of Gallia Lugdunensis. When the Emperor Augustus inaugurated Lugdunum as the capital of Roman Gaul in 18 BC, he did so with a ceremony on 1 August - the same date as the Irish festival of Lughnasadh, said to have been inaugurated by Lug. Other such place-names include Lugdunum Clavatum (modern Laon, France) and Luguvallium (modern Carlisle, England).

Other places which are likely named after him include:

• Lusignan, Loudun and Montluçon in France;
• Lugano, Locarno and Lugarus in Switzerland;
• Loudon in Scotland;
• Dinlleu in Wales;
• Liegnitz in Poland
• Luga in Russia;
• Leiden in the Netherlands;
• Luggude in Sweden;
• Lugoj in Romania;
• Lugo in Italy;
• Lugo in Galicia, Spain.

He is believed to be the god Julius Caesar was referring to when he wrote that "Mercury" was the god most reverenced in Gaul (Gaulish inscriptions to "Mercury" bear out this assertion). Caesar describes the Gaulish Mercury as inventor of all the arts (cf. Lug Samildánach, "skilled in all arts"), patron of trade and commerce, and protector of travellers. His iconography includes birds, particularly ravens; horses; the tree of life; dogs or wolves; a pair of snakes (cf Hermes's Caduceus); mistletoe; shoes (one of the dedications to the Lugoves was made by a shoemakers' guild; Lugus's Welsh counterpart Llew Llaw Gyffes disguised himself as a shoemaker for a time); and bags of money. He is often armed with a spear. His is frequently accompanied by his consort Rosmerta ("great provider"), who bears the ritual drink with which kingship was conferred. Unlike Roman Mercury, who is always a youth, Gaulish Mercury is occasionally also represented as an old man.

Gaulish Mercury is associated with triplism: sometimes he has three faces, sometimes three phalluses, which may explain the plural dedications. This also compares with Irish myth. In some versions of the story Lug was born as one of triplets, and his father, Cian, is often mentioned in the same breath as his brothers Cu and Cethen, who nonetheless have no stories of their own. Several characters called Lugaid, a popular medieval Irish name thought to derive from Lug, also exibit triplism: for example, Lugaid Riab nDerg and Lugaid mac Trí Con both have three fathers.

High places (Mercurii Montes), including Montmartre, the Puy-de-Dôme and the Mont de Sène , were dedicated to him. In Christian times he seems to have been assimilated to the archangel Michael, and many of the former Mercurii Montes became "St Michael's Mounts".

It has been suggested that the Germanic deity Wotan was influenced by Gaulish Mercury.

Lugus has also been suggested as the origin, not only of Lug and Llew Llaw Gyffes, but also the legendary British king Lud and the Arthurian characters Lancelot and Lot.

External links

• Lugus: the Many-Gifted Lord, an essay by Alexei Kondratiev
• Lugus: the Gaulish Mercury