Although easy to write off the fest nozou and fêtes folkloriques as modern inventions, most of the traditional dances of the fest noz are ancient, some dating back to the Middle Ages, providing a way for the community to grasp hold of its past and relish a deep sense of being with ancestors and with place.
On 5 December 2012 the fest noz was added by UNESCO to the Representative List of the Intangible Cultural Heritage of Humanity.
These festivals were a chance for young people to meet and size each other up, on a social level, by their clothes, and to see how quickly they got tired, since dances sometimes continued for a long time and involved complex and swift steps that required effort and skill.
The major study on Breton dancing is "La tradition populaire de danse en Basse-Bretagne", book written from his thesis dissertation, by Jean-Michel Guilcher (new edition by Coop-Breizh, Chasse-Marée/Armen, 1995).
After the Second World War, the Scottish bagpipes (binioù bras) also became common in Brittany thanks to bagadoù (pipe bands) and thus often replaced the binioù-kozh.
To varying degrees, some fest noz groups also use electronic keyboards and synthesisers (Strobinell, Sonerien Du, Les Baragouineurs, Plantec, etc.).