The discipline of International Relations refers to the Peace of Westphalia that ended the 30 Years’ War in 1648 as “the dawn of the modern international system.” The treaties signed in Münster and Osnabrück in 1648 indicate the political and diplomatic development that paved the way to the establishment of international institutions. The Peace of Westphalia ended the feudal system based on the primacy of the Papacy and the Holy Roman Empire and led to the emergence of new political entities called “sovereign states.” Thus, it indeed marked the beginning of an international milieu that would facilitate the emergence of nation-states.

Consequences of the Peace of Westphalia may be summarized as follows:
• First, the peace treaties were negotiated and signed by the states dominated by the rulers that were commonly accepted as sovereigns of their realms.
• Second, the physical borders of each state were recognized and commonly accepted. Therefore, each of these units represented a political entity.
• Third, each sovereign who represented a state was accepted as equal, regardless of the size of lands they ruled or the nobility o which they belonged.
• Fourth,though no international organization emerged as a body until the late 19th century, the way in which these peace accords were made initialized a method that enabled states to communicate collectively through diplomatic instruments. Thus, it is possible to assert that the Peace of Westphalia laid the foundations of collective diplomacy and established the basis of the Congress System that would help institutionalize the international environment in the following centuries.

• Since war existed as a means for state to achieve their interests, the European political system in the 18th century was a royal court in which no monarch could dominate on his own. Though some monarchs had greater reach to power through the richness of the realm they ruled, no ruler had the absolute means to make a marginal difference to subdue the others. Therefore any conflict rested on the interest of a single monarch happened to turn into a war in which almost all units involved attempting to get a share. As Paul Schroeder points out “the motive and rule
of all action was to advance the interests of the state meaning first of all its power, security, and wealth, but also, almost equally, its monarch’s honour and prestige (considération) and rank among other princes. Reason of state thus closely linked the state with its monarch and dynasty, but not with its people or nationality; that link was only beginning to emerge in some countries” (1994: 8).
• Almost all the major conflicts that broke out in Europe were related to royal issues and unsettled dynastic successions, as in the cases of the Wars of the Spanish Succession, the Wars of the Austrian Succession and the Seven Years War. However, war-making was costly and the financial means of the European monarchs only allowed them to wage limited wars with restricted aims.    • Understandably, the Congress System was the direct result of all of the traits mentioned
above. They were convened to end wars and find a way to resolve the conflict and to reach a mutually-acceptable agreement. All the major conflicts which involved almost all the actors in the European political system were settled and resolved by major conferences.
• Basically, the Utrecht Congress was a meeting to end an all-out war and construct a collective rapprochement for peace. In a way, it was an adaptation of the procedures which had worked effectively in the Peace of Westphalia. As had happened in the course of Utrecht, the congresses emerged as adequate platforms to end wars only; however, states were hesitant to apply to this instrument to other international issues. Therefore other congresses that were held in the 18th century had the same characteristics as those of Utrecht, that is, they were all “peace” congresses. In that sense, these were “ad hoc” meetings. 

The French Revolution and the French Revolutionary Wars utterly ended the European balance of power mechanism by destroying the dynastic kinship. The Revolution also distorted the Congress System replacing multilateral diplomacy with bilateral treaties made during the Revolutionary Wars. Since France was a republican regime, the previous dynamics of diplomacy that was depended on dynastic kinships had no longer significance. Therefore, for other major European powers, the war was the only way of interaction with France.

The coalitions against Napoleon were formed through treaties that were “intended to ensure the loyalty of the members of this coalition to one another, to sustain the willingness of its members to fight the war through to a successful conclusion, and to prevent its members from making separate peace with France at the expense of one another” (Rich, 1992: 3). Therefore with such new characteristics, these coalitions were profoundly different from those made in the 18th century since they “contained political, territorial and economic provisions that all members deemed essential to safeguard and promote their individual interests and to ensure the future stability of Europe as a whole” (Rich, 1992: 3). In this respect, the coalitions which in definition had loose characteristics were transformed into alliances with obligatory and coercive features. 

In March 1814, four major powers of Europe, namely England, Russia, Prussia, and Austria came to an agreement and signed the Treaty of Chaumont to form the coalition that would eventually defeat Napoleon. However, due to its characteristics and the commitments made by the signatories, the treaty amounted to an alliance. The signatories reaffirmed their commitments to the previous agreements and decided not to make a separate peace until all other objectives achieved. These “other objectives” defined in secret articles comprised a settlement of a new European system to restore or replace the older system that was utterly distorted by Napoleon. Article 32 of the Treaty of Chaumont required the convention of a general congress within two months following the signature of the treaty by the plenipotentiaries of the belligerents to regulate the arrangements which were to complete the provisions of the peace treaty signed with France (Mowat,1922: 5). The definite aim of the four major powers was to implement the new conditions agreed upon the post-Napoleonic European political system.

The Congress convened in November 1814 in Vienna. Nevertheless, the decision-making process was carried out by the four major powers that were the signatories of the Treaty of Chaumont. Throughout the Congress of Vienna, these powers singlehandedly drew the new European map, dissolved Napoleonic states, restored the old monarchies that Napoleon dismissed and made extensive border changes through annexations (Mowat, 1922: 7-8).

Following the Battle of Waterloo, the major powers signed two separate alliance treaties consecutively, the Holy Alliance and the Quadruple Alliance. The former, signed on 18 September 1815, was a proclamation of the three East European monarchies, that is, the royal houses of Habsburg, Hohenzollern, and Romanov. The scheme of the alliance was proposed by Alexander I of Russia and appeared as a manifesto of absolute monarchy. Its content refers to a spectrum from divine right of the kings that appear in Holy Scriptures to Christianity’s value system in which a king was to rule with justice and love his subjects as the shepherd of a flock or a family father (Mowat, 1922: 23-24). The alliance was proposed as a spiritual formation of the three sects of Christianity. The three monarchs would remain united by the bonds of a true fraternity. With the Alliance, all three monarchs accepted each other as equals and brothers. The monarchs promised to rule their subjects based on Christian values such as charity, justice, and peace as well as to stay united in helping each other to fulfill the role given to them by their God. Under such an agreement, the parties accepted to employ any effective measure toward helping one another. The content of the Holy Alliance was an explicit manifesto for the legitimacy of the absolute monarchy’s sovereignty over the people who had recently experienced wthe French Revolution and the Napoleonic Wars. Almost all European powers were forced to muster huge armies to fight against the citizen army of the French Republic and then Napoleon’s French Empire. Such an experience elevated the submissive subjects of the monarchical regimes to a higher consciousness of liberty and to a sense of nationality. Therefore, the Eastern monarchies built a bloc to counter any liberal or nationalist uprising by their “subjects.” As the three absolute monarchies, Russia, Austria and Prussia formed the foundation of Holy Alliance, all European states were called to adhere to its principles in order to be accepted as equals. Except for England being a liberal monarchy that could not affiliate with the rhetoric of the Holy Alliance, all the other monarchies responded positively to the call and signed the alliance. Following the restoration of the French monarchy, the Holy Alliance was born as the second successful formation of the restoration following the Napoleonic Wars. As such, the rules of the Holy Alliance provided the basis on which the new peace in Europe would be established. However, Britain also decided to join the alliance. As a result, the treaty establishing the Quadruple Alliance was signed on 20 November 1815. However, this does not mean that Britain embraced the values of the absolute monarchies, nor did Britain and other members of the Quadruple Alliance stop seeing France and the effects of the French Revolution as a threat to their regimes. Yet, despite all these, once again, peace came to Europe. 

• The Quadruple Alliance (later Quintuple) that was extended to the peacetime and formed the great power ensemble.
• The periodical congress system that served as an institutional consultation mechanism among great powers to maintain the status quo.
• The diffusion of “promulgation of norms and rules of European public law” that gave “the institutional, territorial, and great-power arrangements in Europe a certain sense of legal-based legitimacy and authority” (Ikenberry, 2001: 98)

• Despite the absence of an international organization, the Concert necessitated extensive communication among European powers. Therefore, the Congress system was reinstituted to solve territorial, political, economic and even colonial issues that could have disturbed the distribution of power. With the restoration of monarchies, the homogeneity among European states was re-established. However, starting from the Congress of Aix-la-Chapelle in 1818, the major powers came to understand that the notion of the classical absolute monarchy was in decline and that power and legitimacy were about to lie with the people rather than with the state. The rapid rise of liberalism and nationalism triggered the 1848 Revolutions, and almost all European monarchies transformed into constitutional regimes. This brought the era of absolute monarchies to an end and deemphasized the dynastic kinship in international politics.
• The congress system introduced by the Concert of Europe was different from the older system (Ikenberry, 2001:105). In the 18th century, conferences occasionally met to end wars and negotiate the terms of peace. However, after 1815, an ongoing series of conferences filled the agenda of European politics. Moreover, these conferences served as a joint management mechanism, establishing a common trend of how territorial disputes could be resolved through negotiations. Moreover, the congress system provided a common understanding with European states to develop a security community within the continent.
• Despite the rise of liberalism and nationalism in the 19th century and the dissolution of absolute monarchies, dynastic kinship still acted as a network in diplomacy. Royal family ties were still functional; international problems were regularly negotiated in royal gatherings. Monarchs were credible mediators for settling international conflicts. However, power shifted to public decision makers within states, and the role of the royals ended (Bridge and Bullen, 1980: 13-15).
• Finally, the Concert system was geographically limited to Europe. Its mechanisms only applied to the European political community. In other words, nonEuropean states were excluded from the collective diplomacy of the 19th century. The Concert, therefore, failed to be based on a universal legitimacy. 

Protocol 23 signed at the Paris Congress provided a reference to a third-party mediation for the resolution of international disputes, although it did not impose mandatory measures on states. (Mowat, 1922:112). Article 15 of the Final Act of the Paris Congress was a remarkable improvement in international institutionalization since it established an international commission for the supervision of the Danube River. The establishment of the International Danube Commission for the regulation of free navigation in the river was the first initiative in forming an international body for the governance of a particular international issue.

The Berlin Congress. 

• The congress system proved to be the best mechanism for mediation and arbitration among European powers. Besides, meeting periodically at the congresses contributed to the construction of a collective identity among Europeans, because the common diplomatic language and codes created shared understandings among states, but the system was confined to Europe. Non-Europeans were neither familiar with the congress diplomacy nor shared a common understanding of diplomacy and customs.
• The Concert contributed to the cooperation among European states for maintaining peace as well as the governance of the system. However, it did not produce permanent international bodies for resolving the disputes. Nor did it contribute to the institutionalization of international regulations and norms by way of codifying them into international law. The Concert never encouraged its members to create further organizations. As such, it was only an instrument of collective diplomacy, not an organizational body to regulate the international system. Its structure was determined by the great powers which produced rival blocks by the end of the century.
• In European politics the congress system served as a tool of peacebuilding after the armed conflicts. However, it failed to prevent the confrontations of Europeans with non-European powers as the cases of US-Spanish War of 1898 and the Russo-Japanese War of 1905 illustrated.               • Although tthe congress system was the primary tool of great power diplomacy, the outcome of the congresses never surpassed the will and interests of their organizers. In other words, the Concert was designed to favor the great powers and contribute to their common interests. Probably, this is the most negative legacy of the Concert for future international organizations, because it undermined the principle of sovereign equality.

The Metric Union (1875), the International Copyright Union (1886), and the International Sugar Union (1902) were the most telling examples of international organizations that were established for regulating the international market. Furthermore, the International Telegraphic Union (1865) ,theUniversalPostalUnion(1874),and the International Union of Railway Transportation (1890) emerged as the key international organizations in coordinating international communication and cross-border transportation. (Schecter, 2010: xxvixxvii). These public international organizations were formed by international treaties among states.

• Collection point and clearinghouses for information
• Centers for collective decisions on the solution of common problems
• Tools for the coordination of national policy and practices
• Agencies for promoting uniform standards in their fields

First Geneva Convention for the Amelioration of the Condition of the Wounded in Armies in the Field in which was signed by twelve countries August 1864.

• The international conventions during the Concert System were ad hoc peace conferences called
for the collective management and resolution of particular international crises. Their outcomes
concerning international norms and international law were not the primary concern. These congresses such as the Paris (1856) and the Berlin (1878) Congresses were rather ‘great power meetings’ and reflected strong characteristics of great power hierarchy of the Concert System.     • The Hague Conference, on the other hand, was the first international meeting that was based on a higher sense of equality among states, regardless of their power status, and more universal representation. All 59 sovereign states were invited to the conference from every corner of the world. Out of its 26 participants, 20 states were from Europe, four from Asia, and two from the Americas. As such, The Hague Conference can be considered as the first global conference in the history of the international relations. It was a universal assembly of states that convened to reach a common compromise for a specific issue, armament, which would be a menace to peace if an action were not taken (Foster, 1904: 14-16).
• Previous international conventions were held in order to resolve specific international crises. However, The Hague Conference was organized to conduct negotiations on a general topic rather than a particular crisis. It did not address any territorial or political problem. Nor did it seek a third- party mediation. Instead, the conference aimed to direct the attention of the invited governments to a collective problem that might pose a threat to all sides if a collective action would not be taken.
• During The Hague Conference, three independent committees were formed to work on these issues: armament, arbitration, and the rules and customs of war. Although this working procedure had been first introduced at the Berlin Congress, the committees proved to be more efficient as the assemblies of state interaction at The Hague Conference. The committees prepared their reports to be discussed in the final meetings of the conference. The final act was the outcome of this procedure, which was successfully conducted for the first time.

The adoption of the Convention of the Pacific Settlement of International Controversies was one of its most significant achievements. The First Hague Convention provided a legal basis for a unique mediation mechanism by neutral states as well as international inquiry commissions for the investigation of international disputes. Moreover, it paved the way for the creation of a Permanent International Court of Arbitration (The Advocate of Peace, 1906: 72). The Conference also produced two other conventions. The first was the codification of the previously-agreed norms and regulations of land warfare, while the second was about the status of the Red Cross regarding the naval warfare. The participant states also agreed upon three declarations concerning the use of certain types of ammunition and weapons in times of war (Choate, 1913: 13). The major outcome of The Hague Conference was the creation of the International Court of Arbitration, which was designed as a permanent international body for states to settle international disputes by judicial means.

The first was the adoption of the Convention relative to the Opening of the Hostilities which provided a formal procedure for states to declare a war. The second was the Convention relative to the Establishment of an International Prize Court which proclaimed the establishment of an international prize court that would deal with the resolution of conflicts related to the status of a captured ship in times of war. The third was the plan to hold a third peace conference in the coming eight years.

Since the Second Hague Conference, there was a growing ‘peace front’ of political and civil society groups advocating the creation of an international organization. Zara Steiner (2000: 265) states that the war acted as a major catalyst for “reform movements within and outside elected governments in both the victorious and defeated states for the reconsideration of the premises on which the ‘old diplomacy’ rested and [they] demanded an overhaul of the diplomatic machinery of the prewar order.” There was a general belief that the prewar governments were primarily responsible for the outbreak of the major war. Particularly in Britain and the US, there were also peace movements consisting of intellectuals, civil pressure groups, and politicians who had adopted an anti-war posture (Wertheim, 2011: 797-834; Laity, 2001: 216-237). According to Wilson’s proposal, the League of Nations was supposed to be a community of democratic regimes which would accept the resolution of disputes through diplomacy and arbitration. The League would act as an assembly of states that would contribute to the development of international law. However, it was designed to be an intergovernmental organization rather than a supranational institution. It was considered a transition from the ‘old diplomacy’ to the ‘new diplomacy’ that would rely on a higher degree of compulsory jurisdiction. It was accepted that the great powers would still act as the core of the post-war system but “power balancing would be replaced by more legal and rule-based mechanisms of power management and dispute resolution” (Ikenberry, 2001: 117).

The main organs of the League of Nations were the Assembly, the Council, and the Secretariat. This structure clearly shows that the League was designed as a global parliament where states would socialize and collectively manage the peace, which was hardly won after four years of total war.

The Permanent Court of International Justice (it was independent from the League but acted as an advisory board), the Permanent Mandates Commission, the Minorities Commission, and several other commissions were under the first category.

The International Labor Organization and the International Health Organization were the two most notable examples of this category. 

The failure of the League to prevent the Italian aggression marked a major blow to the organization. In fact, such crises only demonstrated the weakness of the League, because of the same reasons. First, the great powers were divided so that they were not able to collectively manage the post-war system. The US stayed away from the European diplomacy, and both Britain and France were too weak to counter the revisionist policies of Germany, Italy, and Japan. As it was obvious in the Ethiopian crisis, concessions further showed the weaknesses of the major powers and encouraged the revisionist countries to push their own agendas. Second, both the League and its members were disappointed by the British and French hypocrisy. This situation created a vast gap between the great and small powers and diminished the efficiency of the League. It clearly showed that the great powers prioritized their own self-interests over common interests. Therefore, the League was weakened by the absence of the great power support when the organization was in need of leadership. Third, proposals for strengthening the Covenant and collective security by middle and small states were neglected or rejected by the great powers. After the Ethiopian crisis, the optimism that sustained the League disappeared. The League proved ineffective in taking measures against Germany when it abrogated the Versailles Treaty. After 1936, Germany remilitarized the Rhineland by breaking the rules of the Treaty of Versailles and Locarno Pacts and annexed Austria as well as occupied Czechoslovakia. Hitler destroyed the post-war security arrangements in Europe which the League was supposed to oversee. Furthermore, Germany, Italy, and the Soviet Union intervened in the Spanish Civil War, whereas Japan invaded China. On all these occasions, the League remained ineffective or just stood idly. When Germany invaded Poland in September 1939, there was no application submitted to the League to investigate and take a decision on the issue. The politically important action was taken when Finland appealed to the League for the military assistance against the Soviet aggression in 1939: expelling the Soviet Union from the organization. During the course of World War II, the
activities of the League were interrupted, and neither the Assembly nor the Council held sessions. In the final years of the war, the idea for the establishment of a future international organization was on the Allies’ agenda. In fact, when the United Nations (UN) was established, the League still officially existed. The Assembly of the League held a final meeting in Geneva and declared that all its technical missions and properties were transferred to the recentlyestablished UN. With this declaration, the League officially ceased to exist on 16 April 1946.

The League of Nations cannot be considered as the responsible party for the failures between 1920 and 1939. From its onset, neither its design nor its power matched its responsibility to manage international politics. The effectiveness of the organization was closely tied to the support, coordination, cohesion, and cooperation of its members as well as their mutual understanding of peace. However, this was never achieved. Besides, states were always inclined to protect their own interests rather supporting common goals (MacMillan, 2001: 95). The League was the first international institution that was built on the positive and negative experiences of the previous centuries. However, the post-war system proved to be problematic for the League to sustain multiple contradictory roles. The League was never able to produce regulations and norms for the post-war order and failed to promote the international law. The League also fell short of creating a sense of equality among its members, since it was open to the interference of the great powers. The League evidently showed that international organizations were the most effective ways of institutionalization in international relations. However, it also revealed that states might be reluctant to share their sovereignty with international bodies. Therefore, the League’s potential was circumscribed by state sovereignty, which prevented the organization from receiving the necesssary support to keep the peace. Nevertheless, the League of Nations constitutes a significant case in the history of international organizations. It was the first institution with such a complex structure and designed to operate as an actor with some degree of autonomy. Its legacy, both negative and positive, was instrumental in designing a more advanced organization: the UN.