The Concert of Europe was a particular expression of an international system founded on balance. It was established in Vienna in 1815, and collapsed a century later with the beginning of the Great War. It had characteristics that distinguished it from the order that arose from the Peace of Westphalia in the seventeenth century, and the Treaty of Utrecht in the eighteenth century, even if fundamentally the principles behind it pertained to the balance of power. The Concert brought together “all of the major powers, and only the major powers” (Jean-Baptiste Duroselle); during the Congress of Vienna in 1814-1815, there were five such powers who considered themselves to be mutually worthy of belonging to it: Great Britain, which imposed itself in the wake of the Napoleonic wars as the world’s first power, Russia, Austria, Prussia, and France, who even if defeated remained a central part of the system and, as such, was invited to participate in the negotiations. A century later, Germany succeeded Prussia, and Italy joined the “club,” but not without difficulty; the composition of the Concert thus remained surprisingly stable throughout the entire period, which contributed to the system’s effectiveness.

One of the Concert’s primary innovations was the desire of its promoters, notably Castlereagh or Metternich, to increase contacts at the highest level of sovereigns and ministers, as well as on the lower level of ambassadors, in order to maintain the system, to prevent as well as to resolve conflicts. These new multilateral practices, which found expression in congresses, conferences and meetings, did not rely—as was to be  the case for the LN or the UN—on written rules or permanent structures, but on arrangements that combined flexibility and pragmatism. As the work of Paul Schroeder and Georges-Henri Soutou has shown, they also relied on a base of common values and shared references (Christianity, the monarchical principle, as well as certain liberal values arising from the first-half of the eighteenth century) that facilitated negotiation, and that gave the Concert an “organic” character quite apart from a simple mechanism of balance.

Two distinct periods can broadly be discerned in the history of the Concert of Europe. In the first, lasting until the early 1860s, the system worked fairly well. On the Greek question, or the events involving Belgium or Egypt, the principles on which the Concert was based enabled negotiated solutions, and when there was conflict, it was prevented from spreading to the entire continent. Even the violent and deadly Crimean War, which pitted Great Britain, France and the Ottoman Empire against Russian ambitions over the Bosphorus, remained localized. The Congress of Paris in 1856, which put an end to the war, can be considered as the Concert’s apex. This was also the period when Great Britain, whose continental policy aimed for balance, sometimes engaged against France and sometimes against Russia, thus acting as the arbiter of Europe. The second period is more complex. The logic of the Concert clashed first with the inexorable rise of nationalism, whose revolutionary manifestations had been restrained by the powers until that point in the name of the system’s order and stability. The assertiveness of Prussia in the 1860s—successively victorious over Denmark, Austria and France—and then the birth of the German Empire in 1871, were disruptive elements. Great Britain, which was embarking on colonial conquests, allowed this to happen, as it was not sorry to witness the Second Empire’s collapse, and at any rate did not have the military means to intervene on the continent against the Prussian army.  

A host of factors can explain the final failure of the Concert of Europe in 1914. Firstly beginning in the 1880s, there was the implementation at the request of the German Chancellor Bismarck of alliances in times of peace, and then the gradual construction of rival systems—the Triple Alliance and the Triple Entente—even if only the German-Austrian and French-Russian alliances were truly binding on the military level. It was the full flexibility and effectiveness of the Concert, which was based on the constitution of ad hoc alliances to respond to specific situations, that was thus being challenged. The crisis of the summer of 1914 would undoubtedly not have led to broad conflict if the spiral of alliances, mobilizations, and declarations of war had not been set in motion. More profoundly, it was the entire cultural basis in which members of the Concert recognized one another that was contested in the late nineteenth century, with the assertion of nationalism and new solidarities with racial dimensions—such as Pan-Germanism or Pan-Slavism—that were used to pit Europeans against one another. The system, distorted and circumvented, no longer had the constructive and dynamic power in 1914 that would have enabled it to channel the political, economic and colonial rivalries of the powers.

During the second half of the nineteenth century, European expansion, the creation of colonial empires, and globalization accompanied the exportation of the logic, principles, and practices of the Concert beyond the continent. The Berlin Conference of 1884-1885 defined the rules of the game that presided over the colonization of Africa. The creation of Belgian Congo or the drawing of the borders of Afghanistan in 1893 corresponded, among other things, to the desire to install buffer states between French, British, and German imperialism in Africa, or British and Russian ones in Central Asia. In the aftermath of the unequal treaties of 1858, the Western powers imposed on China the adoption of the diplomatic instruments, codes and practices used by European chancelleries; they also launched common military expeditions when the Boxers attacked their delegations in 1900. Yet at the same time, a host of factors revealed at the dawn of the twentieth century the extent to which the Concert was no longer adapted to the profound changes affecting the system, changes of which European leaders and diplomats were not always aware. These included the emergence of new extra-European powers such as the United States and Japan, the growing importance of economic, financial and cultural factors within international relations, the sudden appearance of new actors—private or public, infra-state or transnational—within an increasingly globalized diplomacy, and the assertion of a new international order founded on law and on the principle of equality among states, as outlined during the international Hague Conferences of 1899 and 1907. This also explains the Concert’s inability to resolve the crisis of the summer of 1914, whose implications very largely surpassed the strictly diplomatic and continental framework from the outset.