You do relise how stupid you sound saying this right? Its akin to saying:
"Ireland as a country? Impossible, that wouldn't fly. Ireland's independence ended with the Acts of Union 1800, more or less. And while it retained a regional identity, making it a national entity would be too much of a stretch."
Just because Brittany, unlike Ireland, lost its war for independence doesn't mean it never had a independence movement. Brittany has always had a sizable group who wanted to break away and still does.
Ooh, starting a post with a personal insult, nice ! I'm sooo sorry if I hurt your little FLB/ARB dreams, Gorgi....
Britanny's independence did end after 1532, and particularly after the French Revolution which substituted to old ideas of provincial identity the new idea of a national identity. While Britanny
could have retained its independence in an ATL (why not indeed), the point of divergence with our timeline would be way beyond the scope of Victoria 2. That's why you find the Blanche Hermine flying in EU3 and not in Victoria or in Hearts of Iron.
Comparing Ireland with Britanny, like you do, is indeed quite a stretch, GP : where are Britanny's crowbar brigades, Britanny's Black and Tans, Britanny's IRB ? As for Britanny always having had a "sizable group who wanted to break away and still does", it does strike me that this "sizable group" never manifested itself in any noticeable way, when compared to Basque or Corsican autonomists, to say nothing of Ireland.
Perhaps you were referring to the brave lads of Atao Breizh, Bezenn Perrot and the Bagadu Sturm, those fine Bretons who thought the Third Reich was better than the Third Republic ? They're the only example of active "independentist" action that I can think of, and they never represented anyone but themselves...
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As for potential breakaway French provinces I'd stick with the French Basque country (as part of Euzkadi) and perhaps Corsica. The other provinces, nah, not if there's supposed to be
some historical reality behind the ahistorical nation.
If you take some French provinces, like Poitou, Burgundy, Provence and Britanny, they all have a rich history of independent or semi-independent entities. They all have cultural specificities harking back to the dawn of man, starting with the existence of regional languages or dialects since in Vicky era public education hasn't stamped these out. They all have architectural specificities, agricultural/gastronomical specialties, and province flags, but steep-sloped roofs, hillside
mas farms and regional headgear do not a nation make IMHO.
So, an independent Britanny in Vicky 2? Sure, if the idea is to do away with historical plausibility to get more nations, why not. In fact, then why stop here, every group of provinces could be played as an independent nation, because at some point of history or other, they probably enjoyed some degree of independence/distinctive identity. The Aquitaine, from Poitiers to Bayonne, comes to mind, and Burgundy, that Middle-Ages heavyweight, should have a chance to spring back from the history books...