- There was no central authority in Brittany for many centuries up to the 9th. Instead, there were a number of regional counts jostling for control. This makes for a nice bit of internal strife between petty noblemen, and plenty of opportunity for behind-the-scenes scheming for power.
- Brittany had more or less the same roots as the Arthurian Britain which the core rules describe, being founded by Romano-British migrants and being of Celtic culture and blood.
- It faced more or less the same threats which the Britons faced. From the East there came Germanic invaders bent on conquest (the Franks, related to the Angles, Saxons and Jutes); from overseas came Viking raiders and later the Normans. Ultimately, there was tragic defeat and suppression.
- The Breton language looks and sounds really cool, full of 'z's and 'h's in interesting places. Viz: "Un urzhiataer zo gantañ", "Ra zeuio ho Rouantelezh."
- If you play as a Bretonnic Knight you get to beat up loads of garlic chewing, frog leg eating, onion wearing, moustache twirling, snail fancying Frenchmen.
- When it was united as the Duchy of Brittany (Dugelezh Vriezh, Duché de Bretagne), one of its earliest Dukes was called Conan.
(I like the French really.)