Nationalism

"Nationalism was the most successful political force of the 19th century.  It emerged from two main sources: the Romantic exaltation of "feeling" and "identity" [see Herder above all on this] and the Liberal requirement that a legitimate state be based on a "people" rather than, for example, a dynasty, God, or imperial domination. Both Romantic "identity nationalism" and Liberal "civic nationalism" were essentially middle class movements. There were two main ways of exemplification: the French method of "inclusion" - essentially that anyone who accepted loyalty to the civil French state was a "citizen".

In practice this meant the enforcement of a considerable degree of uniformity, for instance the destruction of regional languages. The US can be seen to have, eventually, adopted this ideal of civic inclusive nationalism. The German method, required by political circumstances, was todefine the "nation" in ethnic terms. Ethnicity in practice came down to speaking German and (perhaps) having a German name. For the largely German-speaking Slavic  middle classes of Prague, Agram etc. who took up the nationalist ideal, the ethnic aspect became even more important than it had been for the Germans. It is debateable whether, in practice,  all nationalisms ended up as Chauvinistic and aggressive, but the very nature of nationalism requires that boundaries be drawn. Unless these boundaries are purely civic, successful nationalism, in many cases produced a situation in which substantial groups of outsiders were left within "nation-states".

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