History of French

French is a Romance language (meaning that it is descended primarily from Vulgar Latin) that evolved out of the Gallo-Romance dialects spoken in northern France.

The discussion of the history of a language is typically divided into "external history", describing the ethnic, political, social, technological, and other changes that affected the languages, and "internal history", describing the phonological and grammatical changes undergone by the language itself.

Before the Roman conquest of what is now France by Julius Caesar (58–52 BC), much of present France was inhabited by Celtic-speakingpeoples referred to by the Romans as Gauls and Belgae. Southern France was also home to a number of other remnant linguistic and ethnic groups including Iberians along the eastern part of the Pyrenees and western Mediterranean coast, remnant Ligures on the eastern Mediterranean coast and in the alpine areas, Greek colonials in places such as Marseille and Antibes, and Vascons and Aquitanians (Proto-Basques) in much of the southwest.

The Celtic population of Gaul had spoken Gaulish, which is moderately well attested, with what appears to be wide dialectal variation including one distinctive variety, Lepontic. While the French language evolved from Vulgar Latin (i.e., a Latinised popular Italo-Celtic dialect called sermo vulgaris), it was nonetheless influenced by Gaulish. Chief among these are sandhi phenomena (liaison, enchainement, lenition), the loss of unstressed syllables, and the vowel system (e.g. raising [u], [o] → [y], [u], fronting stressed [a], [ɔ] → [e], [ø]/[œ]). Syntactic oddities attributable to Gaulish include the intensive prefix ro- ~ re- (cited in the Vienna glossary, 5th century) (cf. luire "to glimmer" vs. reluire "to shine"; related to Irish ro- and Welsh rhy- "very"), emphatic structures, prepositional periphrastic phrases to render verbal aspect, the semantic development of oui "yes", aveugle "blind", and so on.

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