Active separatist movements in Europe
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The wish of nations to have national homelands is not an irrational one. National self-determination is the spine of the international political system. After the First World War, the League of Nations and the mandate system were partially organized to bring ignorant political entities nearer to acknowledging the dream of a nation-state.
But many political entities continue to only dream of sovereignty. Below is a map of territories with strong nationalist tendencies.
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According to Wikipedia, territories with strong national tendencies are somewhat more numerous.
Albania: Northern Epirus
Azerbaijan: Artsakh
Belgium: German-speaking Community, Flanders Community, Wallonia
Bosnia and Herzegovina: Republika Srpska, Croatian Community of Herzeg-Bosnia
Czech Republic: Moravia, Czech Silesia
Denmark: Bornholm, Faroe Islands
Finland: Åland
France: French Basque Country, Historic Brittany, Northern Catalonia, Corsica, Savoy, Occitania, Provence, Alsace, Brittany, Corsica, Alpes-Maritimes, Normandy, Savoy
Georgia: Abkhazia, South Ossetia
Germany: Bavaria, East Frisia, Lusatia, Rhineland, Schleswig-Holstein, Baden-Württemberg
Italy: Emilia-Romagna, Friuli-Venezia Giulia, Insubria, Liguria, Lombardy, Marche, Piedmont, Mezzogiorno (Southern Italy), Padania (Northern Italy), Sardinia, Sicily, South Tyrol, Tuscany, Trentino, Aosta Valley, Umbria, Veneto
Kosovo: North Kosovo
Lithuania: Polish National-Territorial Region
Macedonia: Albanian community
Moldova: Transnistria, Gagauzia, Taraclia
Netherlands: Frisia, Groningen, Limburg
Poland: Upper Silesia, Kashubia
Romania: Székely Land
Russia: Karelia, Tatarstan, Kaliningrad, Chechnya, Circassia, Karachay-Balkaria
Serbia: Vojvodina, Sandžak, Kosovo
Slovakia: Southern Slovakia
Spain: Andalusia, Aragon, Asturias, Balearic Islands, Basque Country, Canary Islands, Cantabria, Castile, Catalonia, Galicia, León, Navarre, Valencia, Cartagena, Extremadura, Castilla–La Mancha, Murcia, Aran Valley
Switzerland: Jura region
Ukraine: Subcarpathian Ruthenia, Autonomous Republic of Crimea, Lugansk, Donbas, Kharkiv, Novorossia
United Kingdom: Cornwall, Northern Ireland, Scotland, Shetland, Wales, Wessex, Yorkshire, Northumbria, Northern Isles, Orkney, Shetland, Na h-Eileanan Siar, Mercia, Isle of Man