Lesneven has its origins in the immigration from southwest Britain in the fifth and sixth centuries, and the name (Les-an-Even) means "court of Even" in Common Brittonic (Llys-Ifan in Welsh) after an alleged military leader of that period.

[3] Lesneven was the castle-town controlling Léon during the Middle Ages.

The town now functions as a market and service centre for the surrounding rural district.

The municipality launched a linguistic plan concerning the Breton language through Ya d'ar brezhoneg 18 July 2007.

In 2008, 19.08 percent of primary-school children attended bilingual schools.