The province of Nantes has always been an integral part of Brittany. When the French government instituted the current administrative divisions called departments, The Province of Nantes was renamed the department of Loire Atlantic, with similar borders. When the departments were grouped into regions, however, Loire Atlantic was taken away from Brittany and attached to a new group called Pays de la Loire. Neither the Breton people or the Nantais have recognized this, and continue to lobby that it be officially returned. This is why some modern maps of Brittany do not include this province. Here is a banner from a Festival in Guingamp in 2019. It is clearly advocating the reunification of the Nantes region with the rest of Brittany.
I have watched several videos of the parades associated with these festivals. The Breton flag is everywhere, but the French flag is conspicuous by its complete absence.
The most important feature that you will notice is the sharp escarpment which runs from the northwest to the southeast. The city of Gwennrann or Guérande is located in the middle of this ridge. The the south lie the 'white lands', the salt marshes, home of the people that the French call Paludier, and north lie the 'black lands', the peat bogs, home of the people that the French call Metayer. On the peninsula in the southwest, two cities form their own distinct costume areas within this region; Croisic and Pouliguen. Here is Guesdon's map of these costume areas, which is more detailed and accurate than Creston's.
1. The Swamp Dwellers, [Paludier], including the towns of Batz and Guerande, as well as many villages in the area, consisting of the salt marshes and the land immediately surrounding them.
The hats are extremely large, have one side folded up and secured by laces through the top, and are garnished with a ribbon and buckle, and multiple strands of multicolored chenille.
White shirt, white smock with a placket on the chest with hand openings, full Breton style knickers, [bragous bras] tied with a white linen garter, white gaiters, and low yellow deerskin suede shoes. The hat must have been useful out in the sun.
And when widowed, with the fold in front. I have been unable to find a photograph of this, but here is Creston's sketch of the hat and its possible positions. The widower is shown at the bottom right.
For more everyday occasions when not working in the salt pans, aprons with or without bibs were worn, often tied with a solid colored band. The coif consisted of two parts. The undercoif was like a cap, with a rolled edge. This roll was visible when the entire coif was put on.
The coif itself is similar to that of Baud, the emphasis being on the front part and wings, which hung down possibly to the shoulder. If you look just above, you can see the women wearing the plain linen form of this coif. For the dress coif, there are two versions; one for Batz and the villages south of the lagoons, and the other for Saille and the villages to the north.
The dress bodice has wide square armholes and full sleeves with a turned back cuff ornamented with brocade. For unmarried girls the bodice was white with black edging, and is worn with an apron that has no bib, but there is an ornamental ribbon worn around the waist.
For married women, the bodice is more elaborate, and the apron has a bib, in the most dressy version, the bib is stiff and quilted. This is the version which is worn for weddings
I had intended to cover more in this article, but I shall end here, and just give a few more images of the Paludier costume.