Nationalism and independence movements

Nationalism and independence movements are a recurring cause of imperial decline, as subject peoples organise around shared identity to demand autonomy or full sovereignty. Such movements are especially damaging to multinational and overseas empires whose legitimacy rests on dynastic or colonial rule. Examples include the national movements within the Austro-Hungarian Empire, the Balkan and Arab revolts against the Ottoman Empire, and the independence wars that dismantled the Spanish and Portuguese empires.