Interwar International Order

Introduction

The Interwar International Order refers to the political, diplomatic, economic, and institutional system that developed between the end of the First World War in 1918 and the outbreak of the Second World War in 1939. It was shaped by the collapse of major European empires, the peace settlements of 1919–1923, the creation of the League of Nations, the emergence of new states, and efforts to establish a more cooperative international system.

The period initially generated hopes for a stable international order based on collective security, disarmament, national self-determination, and multilateral diplomacy. However, the system faced serious difficulties. Germany remained dissatisfied with the postwar settlement, Italy challenged the distribution of power, Japan pursued expansion in East Asia, and the Soviet Union represented a new ideological and strategic force.

The Great Depression, the rise of fascism and Nazism, and the failure of collective security further weakened the international system. By 1939, the institutions and diplomatic arrangements created after the First World War had failed to prevent another major conflict.

1. Meaning and Historical Context

The term interwar period generally refers to the twenty-one years between the First and Second World Wars.

The international order of this period was not a completely new system. It inherited elements of the European balance of power, imperialism, colonial administration, and traditional diplomacy. However, it also introduced new ideas about international organisation and collective responsibility.

The principal features of the emerging order included:

• The Treaty of Versailles and other postwar peace settlements.
• The League of Nations.
• The principle of national self-determination.
• The Mandate System.
• International disarmament initiatives.
• Economic reconstruction and international financial cooperation.
• The changing balance of power in Europe and Asia.

The interwar order therefore represented an attempt to combine traditional state sovereignty with new forms of international cooperation.

2. The Postwar Settlement and New Political Geography

The First World War destroyed or weakened several major empires.

The German, Austro-Hungarian, Ottoman, and Russian imperial systems experienced collapse or transformation. Their former territories were reorganised through peace treaties, revolutions, and new political arrangements.

New or restored states included:

• Poland.
• Czechoslovakia.
• Austria.
• Hungary.
• The Kingdom of Serbs, Croats and Slovenes, later known as Yugoslavia.
• Finland and the Baltic states, which emerged from the collapse of the Russian Empire.

These changes reflected the principle of national self-determination, but the new borders did not always correspond to ethnic, linguistic, or religious identities. Minority populations became a persistent source of political tension.

The settlement also weakened Germany militarily and territorially but did not remove its economic potential or its position at the centre of Europe.

3. The League of Nations and Collective Security

The League of Nations was the principal institutional innovation of the interwar order.

Its objectives included preventing war, promoting peaceful dispute settlement, encouraging disarmament, and developing international cooperation.

The League provided a forum for states to discuss disputes and coordinate responses to international problems. It also undertook activities concerning refugees, public health, labour standards, and humanitarian affairs.

However, its effectiveness depended on the cooperation of member states. The absence of the United States, the withdrawal of important powers, the unanimity requirement for many decisions, and the lack of an independent military force weakened its authority.

The League achieved some success in resolving limited disputes but failed to prevent major acts of aggression during the 1930s.

4. The Problem of Germany and the Versailles Settlement

The Treaty of Versailles became one of the most important sources of instability in the interwar system.

Germany lost territory, overseas colonies, and military capabilities. Reparations and the war responsibility provision created political resentment.

The Weimar Republic faced criticism from nationalists and extremist groups that portrayed the democratic government as responsible for accepting an unjust peace.

During the 1920s, diplomatic efforts attempted to integrate Germany into the European system. The Locarno Treaties of 1925 improved relations between Germany and several Western European states. Germany joined the League of Nations in 1926.

However, the international economic crisis and the rise of Nazism undermined these developments.

5. The Soviet Union and Ideological Competition

The Russian Revolution of 1917 created a communist state that challenged the capitalist and liberal political order.

The Soviet Union initially faced diplomatic isolation and hostility from several Western governments. It later developed diplomatic relations with European states and joined the League of Nations in 1934.

Communist ideology influenced political movements in Europe, Asia, and other regions. At the same time, anti-communist movements became increasingly influential, particularly among conservative, nationalist, and authoritarian political groups.

The interwar order therefore experienced growing ideological polarisation between liberal democracy, communism, fascism, and other authoritarian movements.

6. The Rise of Revisionist Powers

Several states sought to revise aspects of the postwar settlement.

6.1 Germany

Under Adolf Hitler, Germany rejected the Versailles restrictions, expanded its armed forces, remilitarised the Rhineland, and pursued territorial expansion.

6.2 Italy

Benito Mussolini’s government promoted national prestige, militarism, and imperial expansion. Italy invaded Ethiopia in 1935 and intervened in the Spanish Civil War.

6.3 Japan

Japan expanded its influence in East Asia and occupied Manchuria in 1931. Its military leadership increasingly challenged the existing international order.

These revisionist policies undermined the territorial and political arrangements established after the First World War.

7. International Economic Order

The interwar international economy experienced considerable instability.

7.1 Postwar Reconstruction

European economies faced war debts, damaged infrastructure, inflation, and financial uncertainty. The United States emerged as a major creditor and financial power.

7.2 Reparations and War Debts

The question of German reparations was connected to Allied war debts, particularly debts owed to the United States. International financial arrangements attempted to manage these obligations.

The Dawes Plan of 1924 and the Young Plan of 1929 restructured German reparations and helped stabilise the European economy temporarily.

7.3 The Gold Standard

Many countries attempted to restore or maintain the gold standard. However, the system became increasingly difficult to sustain amid financial instability, unemployment, and the Great Depression.

7.4 The Great Depression

The global economic crisis beginning in 1929 weakened international trade and financial cooperation. Protectionism, unemployment, and political instability intensified, undermining the foundations of the interwar order.

8. Disarmament and International Diplomacy

Disarmament was an important objective of the postwar system.

The Washington Naval Conference of 1921–1922 attempted to limit naval competition among major powers. It produced agreements regulating capital ships and addressing security issues in the Pacific.

The Geneva Protocol initiative of 1924 sought to strengthen peaceful dispute settlement and arbitration, although it did not enter into force.

The Kellogg-Briand Pact of 1928 committed its signatories to renounce war as an instrument of national policy, subject to the pact’s wording and the unresolved question of enforcement.

The World Disarmament Conference, which began in Geneva in 1932, failed to achieve a comprehensive agreement.

These initiatives demonstrated the growing importance of multilateral diplomacy but also revealed the difficulty of reconciling national security interests with arms reduction.

9. The Collapse of the Interwar Order

The international order deteriorated during the 1930s through a series of crises.

• Japan occupied Manchuria in 1931.
• Germany withdrew from the League of Nations in 1933.
• Germany reintroduced conscription in 1935.
• Italy invaded Ethiopia in 1935.
• Germany remilitarised the Rhineland in 1936.
• Germany annexed Austria in 1938.
• The Munich Agreement of 1938 permitted Germany to occupy the Sudetenland.
• Germany occupied the remaining Czech lands in March 1939.
• Germany invaded Poland on 1 September 1939.

These developments exposed the weakness of international institutions and the reluctance of major powers to confront aggression at an early stage.

10. Why Did the Interwar Order Fail?

Several interconnected factors contributed to its collapse.

10.1 Unresolved Grievances

The postwar settlements created resentment among defeated and dissatisfied states.

10.2 Weak International Institutions

The League lacked the political and military capacity to enforce its decisions against powerful aggressors.

10.3 Nationalism and Extremism

Fascist and Nazi movements rejected liberal democracy, international cooperation, and important aspects of the postwar settlement.

10.4 Economic Crisis

The Great Depression weakened democratic governments and encouraged protectionist and expansionist policies.

10.5 Failure of Disarmament

Major powers remained unwilling to reduce military capabilities when they believed their security was threatened.

10.6 Appeasement

Britain and France adopted policies of accommodation towards some German demands, partly because of war exhaustion, military limitations, and the belief that certain grievances could be addressed peacefully. The policy ultimately failed to prevent German expansion.

10.7 Conflicting Great-Power Interests

The major powers did not develop a consistent strategy for defending the postwar order. Their divisions created opportunities for revisionist states.

11. Historical Significance

The interwar period provides an important case study in the relationship between international institutions, state interests, economic stability, and security.

It demonstrated that peace treaties alone cannot guarantee a stable international system. Durable peace requires legitimacy, cooperation among major powers, credible enforcement, and an economic environment that supports political stability.

The failures of the interwar period influenced the design of the United Nations and the post-1945 international economic institutions.

12. Significance for International Relations and Pakistan

The interwar order is relevant to Pakistan’s study of international institutions, collective security, international law, and the politics of great powers.

It illustrates the difficulties smaller states face when international rules are not supported by the major powers. It also demonstrates the importance of multilateral institutions in providing diplomatic forums for states that cannot independently shape the international balance of power.

The experience of the League of Nations and the interwar order remains relevant to contemporary debates about the effectiveness of the United Nations and the future of multilateralism.

Conclusion

The interwar international order was an ambitious attempt to build a more peaceful and cooperative system after the First World War. It introduced the League of Nations, new diplomatic arrangements, international disarmament initiatives, and a reorganisation of the political map.

However, unresolved territorial disputes, ideological conflict, economic instability, nationalism, and great-power rivalry undermined the system. Its collapse in 1939 demonstrated that international institutions cannot maintain peace without the political commitment and cooperation of powerful states.

Key Takeaways

1. The interwar period extended from 1918 to 1939.
2. The postwar settlement transformed Europe’s political geography.
3. The League of Nations was the principal institutional innovation.
4. The Treaty of Versailles created lasting German resentment.
5. The Soviet Union introduced a powerful alternative ideology.
6. Germany, Italy, and Japan challenged the postwar settlement.
7. The Washington Naval Conference attempted to limit naval competition.
8. The Kellogg-Briand Pact renounced war as an instrument of national policy.
9. The Great Depression weakened international cooperation.
10. The League failed to prevent major acts of aggression.
11. Appeasement and conflicting great-power interests contributed to the system’s collapse.
12. The failure of the interwar order influenced the creation of the United Nations.

Review Questions

1. Define the interwar international order and identify its main features.
2. How did the First World War transform Europe’s political geography?
3. Explain the role of the League of Nations in the interwar system.
4. Why did Germany remain dissatisfied with the Treaty of Versailles?
5. How did the Soviet Union affect ideological competition?
6. Discuss the role of disarmament initiatives in interwar diplomacy.
7. How did the Great Depression weaken the international order?
8. What factors led to the collapse of the interwar system?
9. What lessons does the interwar period offer for contemporary international relations?

Further Reading

• Encyclopaedia Britannica: Interwar Period
• United States Office of the Historian: The Paris Peace Conference and the Treaty of Versailles
• Encyclopaedia Britannica: League of Nations
• Zara Steiner, The Lights that Failed: European International History 1919–1933.
• E. H. Carr, The Twenty Years’ Crisis, 1919–1939.