Before 1848, nationalism was a revolutionary ideology, often concerned with rebelling against autocratic forms of government or against external rule. Romantics saw in the shared history and culture of particular peoples an argument for the overthrow of imperial domination. Liberals linked nationalism to economic progress and the protection of individual liberty, convinced that both could be achieved only if the will of the people was expressed through representative government. In the second half of the nineteenth century, however, conservative leaders such as Germany’s Otto von Bismarck harnessed the power of nationalism to garner support for conservative, even reactionary, governments and policies. While nationalism served as a catalyst for political unification in Italy and Germany, just as often it led to division and conflict. The United States fought a bloody and bitter civil war between 1861 and 1865 over the power of the federal government to stop the expansion of slavery. France went from the Second Republic to the Second Empire, and then faced the secession of Paris from France in 1871. Conflicting nationalisms undermined the strength and stability of the Austro-Hungarian Empire. Toward the end of the century, the adoption of nationalism as the basis for personal identity led to horrifying violence against perceived outsiders, particularly Europe’s Jewish population. The Dreyfus affair in France (1894–1906) spurred a Jewish nationalist movement—Zionism—as some members of Europe’s Jewish community became convinced that lasting peace and security for Jews could be achieved only through the foundation of a Jewish nation-state. ■