In 1899, an international conference began in The Hague on the initiative of Russia, with the general objective of “seeking the most effective means of ensuring to all peoples the benefits of a real and lasting peace.” Three subjects were on the agenda: arms control, troops, and military budgets; the implementation of conventions seeking to reduce, during times of war, the use of the deadliest weapons, as well as pointless suffering; and the recognition, for cases that lent themselves thereto, of the principle of arbitration “in order to prevent armed conflict between nations.” Even though Russia’s intention was, more mundanely, to avoid an arms race with Germany that it did not have the means to pursue, the conference gave rise to great hopes in Europe and across the globe. It was followed by another in 1907, again in The Hague, which had an even greater impact. A third was planned for 1915 but could not be held due to the war.
The results of the two conferences seem limited at first glance, as they were not followed by any concrete effect in matters of disarmament. The measures aiming to humanize war, along with its practices and customs, indeed represented a first attempt at codifying jus in bello (the series of rules governing conduct in time of war), but remained general and not particularly restrictive, as they notably did not prevent Germany and a series of other belligerents from using poison gas during the First World War. The conference of 1899 decided to create a Permanent Court of Arbitration, still active today, which at the time was the first international institution offering legal solutions for disputes between states, without for all that drawing up a list of cases for which the signatories would be required to resort to the court. The court was located in the Peace Palace in The Hague, which was built thanks to donations from the Carnegie Foundation; it was inaugurated in 1913, one year before the outbreak of the Great War.
Yet what would prove to be essential resided elsewhere. The two conferences inaugurated, on a global scale, the era of institutional multilateralism, orchestrating new actors and introducing profoundly innovative principles within international relations. The first conference lasted 72 days and brought together delegations from 26 states, 19 of which were from Europe; the second one was less Eurocentric and much more universal, bringing together 43 nations over the course of 140 days, or nearly 300 participants, with Latin American countries this time making the journey. This totally unprecedented configuration raised major problems with regard to organization, logistics, protocol, and confidentiality. While the official language remained French, people did not hesitate to also express themselves in English or Spanish. It was often in improvising that some of the practices of the multilateralism that would be at work two decades later within the League of Nations were first tested out: the division of work in commissions and sub-commissions, the search for compromise, rapprochements of circumstance, never-ending speeches and passionate debates, public sessions and secret negotiations, all within an official context or in the function rooms of the hotels where the delegations were lodging. Public opinion flared up surrounding the debates, while the press had its accredited journalists. In 1907 they were provided with a daily communiqué, while the public could watch certain sessions in their entirety from the stands in the Binnenhof’s large Hall of Knights.
Delegations essentially consisted of diplomats and an almost equal share of experts, whose presence was made indispensable by the sometimes-technical nature of the debates: military staff for questions connected to disarmament on both land and sea; jurists for clauses relating to arbitration and the codification of jus in bello. Never had the use of experts in connection with international conferences or congresses—a practice that was already well established during the early modern period—reached such a scope. The French delegation in 1907, led by Léon Bourgeois, Paul d’Estournelles de Constant, and Louis Renault (three future winners of the Nobel Peace Prize), numbered 15 members, including five members of the military and two jurists (Renault and Henri Fromageot), while of the 14 members in the Russian delegation, there were four members of the military and as many jurists. The same was true for Great Britain, Germany, the Netherlands, Switzerland, Sweden, Argentina, and Cuba. Some renowned jurists, such as the Russian Frédéric de Martens, the Belgian Édouard Descamps, the Dutchman Tobias Asser, or the Argentinian Luis Drago, guided the debates, gave numerous interviews, and stole the limelight from delegation leaders. For that matter, diplomats did not hide their concern over seeing these experts encroach on their prerogatives, or sometimes establish intellectual solidarities among themselves which escaped the political logic of the Concert of Europe.
Running counter to an international system founded on the balance between major European powers, which Léon Bourgeois and d’Estournelles believed to be profoundly corrupted by the game of alliances, the Hague Conferences sought to rely on law in order to guarantee peace. Through a number of characteristics (their universal nature, the affirmation of legal equality between states whatever they may be, the search for compromise and a unanimous vote) they announced—for the best as well as the more debatable—the principles that would be at work in the LN, for which Léon Bourgeois served as the first Council president in 1920. Article 27 of the Convention of 1899 on arbitration, which was requested by the French delegation, introduced the notion of “duty,” and therefore of moral obligation, in international relations. By stipulating that “the Signatory Powers consider it their duty, if a serious dispute threatens to break out between two or more of them, to remind the latter that the Permanent Court is open to them,” for the first time it created, in the words of Léon Bourgeois, a “contractual link of solidarity” between states. Many clauses adopted or considered at The Hague were extended into the 1920s in a more favourable context: the Convention of 1899 “concerning the laws and customs of war on land” was followed in 1925 by the Geneva Protocol banning the use of chemical and biological weapons, as well as the Geneva Conventions of 1929 regarding the treatment of prisoners of war. The International Court of Justice which failed to be created in 1907 for lack of agreement on how to nominate judges, was established in 1922 within the framework of the LN. The Hague Conferences thus established themselves during the modern period as an essential and foundational stage in the history of the legal regulation of international relations and, more generally, of peace.