*Lugus is a funny case. Over the development of contemporary Gaulish polytheism(s), it’s been a granted that *Lugus is an important God among all Celts.

However, there is no certain attested dedication to Him in Gallia, and the one in Celtiberia may also be doubtful. Instead, we have the plural Lugoves in inscriptions; one in the nominative and the others in the dative.

If He was THAT important, you would figure He’d have a singular dedication *at least* once in Gallia. Toponyms and theophoric names are used in the argument for His existence, but this also has issues. Theonyms are comprised of nouns which have a meaning outside of the God itself. ‘Lug-‘ is also debated on it’s meaning. Koch asserts that it pertains to ‘oath’. Pseudo-Plutarch says it’s ‘Raven’. And there are more options besides these.

So even Lugudeca, Lugdunum and other examples can be argued to be something other than pertaining to the God *Lugus.

Scholars attempt to utilize Insular Lugh and Llew to establish a continuum between the Continent by way of tenuous imagery and unattested Interpretatio (shoes, shoe makers, alleged triplicity and Mercurius). There’s also Segomâros who points out Gallo Roman offerings at Lugudunum at the beginning of August, which were part of the Imperial cultus. This coincides with Lughnasadh.

My own opinion is middling. If the singular *Lugus is a thing, but just isn’t attested in Gallia, I think it’s possible His cult was developed late. Or perhaps His absence is due to fear of evocatio like Koch implies. Or theonymic scribal taboos with certain allowances.