Following a quarter-century of revolutionary upheaval and war spurred by Napoleon’s imperial ambitions, the Great Powers met in Vienna in 1814–1815 to re-establish a workable balance of power and suppress liberal and nationalist movements for change. Austrian Foreign Minister Klemens von Metternich led the way in creating an informal security arrangement to resolve international disputes and stem revolution through common action among the Great Powers. Nonetheless, revolutions aimed at liberalization of the political system and national self- determination de ned the period from 1815 to 1848.
The revolutions that swept Europe in 1848 were triggered by poor economic conditions, frustration at the slow pace of political change, and unfulfilled nationalist aspirations. At first, revolutionary forces succeeded in establishing regimes dedicated to change or to gaining independence from great-power domination. However, conservative forces, which still controlled the military and bureaucracy, reasserted control. Although the revolutions of 1848 were, as George Macaulay Trevelyan quipped, a “turning point at which modern history failed to turn,” they helped usher in a new type of European politics and diplomacy. Conservative leaders, exemplified by Napoleon III of France, used popular nationalism to advance state power and authoritarian rule. Further, the Crimean War (1853–1856), prompted by the decline of the Ottoman Empire, shattered the Concert of Europe established in 1815 and opened the door for the uni cations of Italy and Germany. Using the methods of Realpolitik, Cavour in Italy and Bismarck in Germany succeeded in unifying their nations after centuries of disunity. Their policies of war, diplomatic intrigue, and, in Bismarck’s instance, manipulation of democratic mechanisms created states with the potential for upsetting the balance of power, particularly in the case of Germany.
Following the Crimean War, Russia undertook a series of internal reforms aimed at achieving industrial modernization. The reforms succeeded in establishing an industrial economy and emboldened Russia’s aspirations in the Balkans. They also led to an active revolutionary movement, which employed political violence and assassinations and was one of the driving forces behind the 1905 Russian Revolution. After the new German Emperor Wilhelm II dismissed Chancellor Bismarck in 1890, Germany’s diplomatic approach altered signi cantly, leading to a shift in the alliance system and increased tensions in European diplomacy. Imperial antagonisms, growing nationalism, militarism, and other factors resulted in the development of a rigid system of alliances. The Great Powers militarized their societies and built up army and naval forces to unprecedented levels (fed by industrial and technological advances), while at the same time developing elaborate plans for the next war.
The long-anticipated war finally came in the summer of 1914. The assassination of the heir to the Austrian throne in Sarajevo forced the political leaders of the Great Powers, locked in the rigid structure of the Triple Entente versus the Triple Alliance, to implement war plans that virtually required the escalation of hostilities. The ensuing Great War revealed the aws in the diplomatic order established after the uni cations of Germany and Italy, but more importantly, it produced an even more challenging diplomatic situation than that faced by the diplomats in 1814–1815.