Moreover, being in isolation and receiving relatively few travelers from land (due to the paucity of roads leading out, and the poor quality of those existing roads) and from sea (due to the rough conditions of the waters around the peninsula), the culture developed in its own singular ways. Druidical practices lingered on in Brittany for centuries after the Romans wiped the worship of nature, via blood-sacrifice, from England, and Breton conteurs, or bards, practiced their songs up through the 17th century, and pre-Christian elements in the veneration of the saints still exists today, both on Earth-616 and on Earth-Prime.
One of these cultural practices peculiar to the Bretons is the art of cloak-fighting. Brittany being an economically-backwards area, it had always lagged behind in weapons technology, its hardscrabble soil producing very little iron and its inhabitants, for a long time, acquiring steel only through extremely costly trade or from the corpses of foreigners slain in battle - an unusual occurrence, to say the least, for the Bretons, although tough, were always far outnumbered in battle and were ignorant of more civilised battle-tactics. So, like the peasants of Japan and China and Brasil and like peasants everywhere, the Bretons made a virtue out of necessity, and learned how to fight with simple farming and fishing tools, and developed a few unique forms of fighting: an acrobatic style of kick-fighting that made equal use of feet, knees, and elbows; a brutal form of wrestling that gave primacy to manipulating pain- and pressure-points; and cloak-fighting.
The origins of cloak-fighting are obscure, although there are various Breton folktales regarding its creation by Lancelot, who is usually credited with having created it to fight against the Ankou, the driver of the spectral cart who arrives, on the last night of the year, to collect the last person to die that year. The Ankou is either a tall, haggard man with long white hair, or a skeleton with a revolving head who sees all people and all things; in either case his touch is death. The Ankou (so the story goes) arrived to collect the soul of Jean-Claude, Lancelot's best friend, and so Lancelot, desperate to fight off the Ankou (who was, of course, the best swordsman this life or the next had ever seen - greater even than Lancelot himself) had the idea to use his cloak as a weapon, and with that fought off the Ankou until dawn came and the Ankou was forced to flee.
A cloak-fighter traditionally (for the skill has all but died out, now; the emigration of the Bretons during the 19th century, in the face of extraordinarily crushing poverty and famine, scattered most of its practitioners across the continent and to America, and few thought to continue its practice, or teach it, outside of Brittany) trained for years; the skill is clumsy, awkward and initially useless, but lethal in the hands of an expert. A cloak-fighter wears a long, thick cloak that reaches to their ankles and almost, but not quite, touches the ground, each fighter wearing a cloak designed specifically for him or her (one of the reasons the skill died out is that a fighting cloak, unlike a sword or spear, cannot be handed down from father to son); typically the cloth of the cloak is heavy and tough, and the outside of the cloak lined with hide or fur or something equally capable of resisting damage. The edges of the cloak, both sides and bottom, have something sharp and hard sewn into them, to give the cloak its edge. In centuries past, when iron and even bronze were in relatively short supply, wood and bone were most often used, but as time went by and metals became more available, they replaced those cruder alternatives. A cloak-fighter whips the edges of his or her cloak around, using his or her strength to build up enough speed so that the heavy and sharp edge of the cloak will strike with deadly force. While the battle cloaks would not be proof against full plate armor, with enough speed and force the edge of a cloak could pierce chainmail, which was far more common among French soldiers.
Cloak-fighters had a long and distinguished history among the Bretons, never more so than in the fight against the wizards of the Isle de Groix. In 913 C.E. a group of mystics, sorcerers and magicians, tired of the constant threat of destruction by Vikings and other raiders, as well as the fear and hatred shown to them by both common man and king - except, of course, when the latter wanted to make use of them - held a meeting on the Isle de Groix, off the southern coast of Brittany, and formed the Order d'Isle de Groix, whose stated aim was the spreading their particular school of magic to as many students as possible and, eventually, the conquering the Earth and the punishment of their enemies.
The Isle de Groix, a six square mile island just south of the village of Lorient, held sea caves and dolmens of unknown origin, and was full of potential magical energy, and so the Order, making use of the magic in the island's soil and the energies trapped in the dolmens, erected a magical keep there. They then began attempting to extend their rule, trying to terrorize the local Bretons and extort food and women from them. They were met first by the organized resistance of the cloak-fighters (wizards can be killed, if they are struck quickly enough, before they have time to cast a spell, and even the most powerful mage cannot maintain a defensive shield forever) and later by other, more powerful wizards and orders, such as the School of Ancient Ways. The Order d'Isle de Groix struggled for decades to overcome their enemies, but never succeeded in gaining more than a foothold on the continent (although they were much feared at sea, both in the Bay of Biscay and in the English Channel). Their point of greatest influence came in 1210 C.E. when their strongest student ever, the Sieur R'Harmys, delivered a challenge to the Chinese sorcerer commonly known as Genghis, as a way to decide whose school would have primacy in the world. Genghis, given great power by the Vishanti almost four millennia ago, defeated R'Harmys, and the influence and power of the Order began a slow decline, finally ending in its destruction by another evil sorcerer, the Eldritch One, in 1310 C.E.
The Challenger, for his part, had learned cloak-fighting from what was, in all likelihood, the last living teacher of the art. The Challenger, following the death of his parents in a drive-by shooting, had traveled the world, schooling himself in all the ways in which humans could be killed, so that he might avenge his parents. While learning savate from a reformed thief in a dock bar in the bad side of Marseille, the man who would later become the Challenger was told of cloak-fighting, and, intrigued, traveled to Brittany to learn the skill. He found, in a tiny village near Douarnenez, an aging, bald man, who stood straight and tall despite his years, and who, after an initial suspicion of the grim-faced American, was gratified to teach the skill to so astute and eager a student.
Author's Note: Although the history and culture and mythology of Brittany are as given here, cloak-fighting is not a Breton invention, nor was there ever (to the best of my knowledge) anything like the Order de l'Isle de Groix.