IB/Group 3/History/Route 2/Causes, Practices, and Effects of Wars/The Causes of World War II

The causes of World War II are complex, and so we have divided the key themes. The first section is the failure of collective security in preventing the outbreak of war, along with the impact of the Great Depression in Europe in the 1930s. The second section will look more specifically at Hitler's policies as a cause of war, and how the European powers responded to the threat that Nazi Germany posed to Europe.

The failure of 'Collective Security'
One of Wilson's Fourteen Points led to the creation of the League of Nations, an organisation that sought to prevent another war breaking out between states.

""[The League of Nations Covenant] proposed an alternative to the conventional international order, which Wilson was convinced, had been sustained by force. This had created a dangerous arms race and imperialistic activities abroad. Now military power and expansionism were to be replaced by a rule of law in which 'world public opinion' rather than alliances and armaments would be the key to international order.""

- Akira Iriye, The Globalising of America 1913–1945, 1993.

In the 1920s and 1930s, the League faced many changes. Although it was successful in some areas, the overall failure of European states to work collectively through the League in dealing with various international crises was a major cause of World War II.

Structure of the League of Nations
One of Wilson's Fourteen Points led to the creation of the League of Nations, an organisation that sought to prevent another war breaking out between states.

"[The League of Nations Covenant] proposed an alternative to the conventional international order, which Wilson was convinced, had been sustained by force. This had created a dangerous arms race and imperialistic activities abroad. Now military power and expansionism were to be replaced by a rule of law in which 'world public opinion' rather than alliances and armaments would be the key to international order."

- Akira Iriye

In the 1920s and 1930s, the League faced many changes. Although it was successful in some areas, the overall failure of European states to work collectively through the League in dealing with various international crises was a major cause of World War II.

Collective security and the League of Nations
The principle of collective security was the idea that peace could be preserved by countries acting together – collectively – to prevent one country attacking another. Collective security was to be made practically possible by the machinery of the League of Nations. When there was a dispute between countries they would refer the issue(s) to the League's Assembly. If that body could not find a resolution, the Council could then apply 'collective security', i.e. as a group impose moral pressure then economic sanctions, to force the country that was deemed to be in the wrong to comply with its decisions.

The Covenant of the League of Nations
The League met for the first time in Geneva in December 1920. Its key objective was to keep the peace and avoid future conflict by advising on and settling international disputes. It also aimed to promote disarmament, supervise the mandated territories and promote international good will and cooperating through its various organisations dedicated to social and economic development. The initial membership of the League was 32 Allied states and 12 neutral states; however, by 1926 all ex-enemy states had joined. The USSR was not admitted until 1934, and the USA never joined.

There were 26 articles in the League's Covenant (including amendments made in December 1924), which prescribed when and how the League was to operate.


 * Articles 1–7 were concerned with the membership and organisation of the League, its Assembly, Council, and Secretariat.
 * Articles 8–17 were concerned with the prevention of war.
 * Articles 18–21 concerned treaty obligations and the League's expectations of its member states.
 * Articles 22 concerned the mandated territories.
 * Articles 23 concerned humanitarian issues such as labour conditions, the trafficking of women, children, and drugs, health issues, and the arms trade.
 * Articles 24 concerned the commissions.
 * Articles 25 promoted the Red Cross.
 * Article 26 set down how amendments to the Covenant were made.

Dealing with international disputes
It was set down in the Covenant that member states should refer their disputes to one of the following:


 * The Permanent Court of International Justice.
 * Arbitration (having a neutral person or group of people listening to and judging a dispute).
 * An investigation or enquiry by the Council.

If member states failed to refer their dispute to the League, or failed to follow its recommendations, the League could then impose economic sanctions, the mail tool for the League against aggressors. In the aftermath of World War I, in which the economic blockade of Germany had been effective, this economic weapon appeared to have the most potential to be effective in foreign compliance with the League's decisions.

In theory, the League could call for military sanctions as a last resort against an aggressor. Yet the League did not have its own armed forces, and in reality members states did not want to put their sovereign forces under international control. In addition, the Covenant was rather ambiguous as to when and how such armed forces should be used. France had wanted an armed force, or League Army, but Britain had resisted this option. Thus in reality, the League lacked military teeth.

Changing membership of the League
The changing membership of the League reflected the priorities of its leading members, as the more liberal governments of the 1920s became increasingly polarised following the Wall Street Crash and ensuing Great Depression. As right-wing governments within the League became more aggressive, so the perceived threat from the USSR shifted to the Axis powers.

Absence of major powers
The absence of major powers from the League of Nations had a decisive impact on the working and influence of the League; indeed, this is possibly the key reason for why the League ultimately failed to prevent another war.

The most important major power was the USA. The League had been the idea of the Americans and had been championed by President Woodrow Wilson. The US Congress, however, was too concerned that the League would drag the Americans into more disputes and conflicts in Europe, hence the country withdrew into isolationism. The USA had played a pivotal role in bringing World War I to an end, but it did not want to play such a central role in the controversial Versailles settlement.

The absence of the USA seriously weakened the potential of the League to use 'collective security' against aggression, for several reasons. First, the most powerful economic country in the world would have given the League's economic sanctions real weight; the US absence undermined this one essential weapon. Second, without the USA the make-up of the permanent members was distinctly European (except for Japan), and lacked the appearance of a genuinely 'worldwide' organisation. Third, it highlighted that the new organisation might be sidelined in favour of old-style agreements and treaties, as this was clearly how the USA was going to secure its future relationships. Finally, these factors meant that the League was primarily led by European powers that were arguable in decline.

Absence of the USSR
The USSR was excluded from the League of Nations. The newly established Bolshevik government was regarded as a 'pariah state'; indeed, Western powers had invaded Russia during the Russian Civil War (1918–21) to join the 'White' counter-revolutionary forces. As the Bolsheviks consolidated their position in the Soviet Union after winning the civil war, the old powers of Europe looked on with great concern. Afraid that the 'revolution of the proletariat' would spread, they felt that it was expedient to isolate the Soviets rather than to embrace them in a new organisation designed to prevent conflict.

Yet the exclusion of Russia further weakened the standing of the League, as it could be perceived by the USSR as a 'club for capitalists' – an organisation to protect and promote t heir interests and empires at the expense of the exploited masses. Indeed, Lenin viewed the League as 'a robbers' den to safeguard the unjust spoils of Versailles'.

Absence of Germany
Germany was initially excluded from the League. This exclusion again undermined the idea of the League and, perhaps more importantly, suggested that the League was something of a 'victors' club – the four permanent members of the Council were the victorious Allies. In addition, the exclusion tended to ignore the important fact that Germany remained a strong power at the conclusion of World War I. The assumptions that there had been a clear victory over Germany and that there was now scope for a re-ordering of European politics were flawed. Germany had been militarily defeated in the west, but not in the east. Its expansionist politics had not evaporated, nor had its economic power. It would therefore seem, particularly with hindsight, vital that Germany be included in the League so that it could work towards its aim of revising the Treaty of Versailles within the confines of the League's machinery. Following the wave of optimism and positive thinking that ensued after Locarno, Germany was admitted into the League in September 1926.

Weakness of Central European states
The Austro-Hungarian Empire had collapsed following World War I, and had been replaced by a number of smaller states based on the principle of nationality. However, as mentioned earlier, many of these states struggled politically and economically to achieve stability. This meant that instead of another large European state there were now several much smaller states that would require more support from the League, particularly in terms of economic development and territorial security. These states could not offer the League much tangible support in return.

Peacemaking 1920–25
Throughout the 1920s, the League dealt with various disputes arising mainly from the territorial changes of the Versailles settlement. The League had both success and failures in its handling of these disputes. Aaland, 1920 – These islands were populated mainly by Swedes, but following the collapse of the Russian empire, Finland claimed sovereignty over them. The conflict was taken to the League and Sweden accepted the League's decision to give the islands to Finland.

Aaland, 1920
These islands were populated mainly by Swedes, but following the collapse of the Russian empire, Finland claimed sovereignty over them. The conflict was taken to the League and Sweden accepted the League's decision to give the islands to Finland.

Vilna, 1920–23
Both Poland and Lithuania wanted control of the town of Vilna. It had once been the capital of Lithuania, but its people were Polish. The League was unable to prevent the Poles from seizing and retaining it by force. Finally the Conference of Ambassadors awarded Vilna to Poland.

Upper Silesia, 1921
Both Germany and newly formed Poland wanted control of the two important industrial area of Upper Silesia. The League decided to split the rea between the two.

Cofru, 1923
Three Italian army officers were shot while working on a boundary dispute between Greece and Albania. Mussolini blamed Greece and ordered compensation. When the Greeks did not pay, Italian soldiers occupied Corfu. Greece appealed to the League, but the Italian government ignored the Council's ruling and left only when compensation had been paid.

Mosul, 1924
The area of Mosul was claimed by both Turkey and Iraq. The League considered the problem and awarded the area to Iraq, a decision that was accepted.

Bulgaria, 1925
Following a Greek invasion of Bulgaria, the League ordered both armies to stop fighting. An investigation by the League blamed Greece for starting the dispute and ordered it to pay damages. Greece accepted the blame and was ordered to pay compensation.

P. M. H. Bell argues that even though the League did not solve all disputes successfully:

"What was important was that the League had settled down as a valuable forum for the conduct of international affairs. Germany was admitted in 1926, and at once became a permanent member of the Council; so the League was no longer a 'League of victors'. By 1928 every European state was a member (except the USSR). Nearly every foreign minister made a point of attending its sessions. The League was still young, but there seemed a good change that Europe had found a workable successor to the pre-1914 state system."

- P. M. H. Bell

Attempts to strengthen the League
Two attempts were made, in 1923 and 1924, to strengthen the machinery of the League of Nations. These were both initiated by France. The first of these initiatives was the Draft Treaty of Mutual Assistance, which would have required all members of the League to come to the assistance of a victim of aggression. Next, the Geneva Protocol of 1924 would have made arbitration compulsory in all disputes. Both initiatives were rejected by Britain, its Dominions and the Scandinavian powers, who believed that members would not be willing or able to carry out a huge commitment that would result from such a role.

The League thus remained divided between those states that wanted a strong League to enforce the existing territorial agreements, and those that wanted to be more selective in dealing with aggression. This division also arose because of the difference in vulnerability of the various states. While France felt highly vulnerable, others were not so worried and were not prepared to take on what they saw as extra commitments. These differences were to be highlighted further by the Ruhr Crisis, which would deeply undermine the principle of collective security.

The Ruhr Crisis (1923)
For France, the future security lay in upholding the terms of the Treaty of Versailles. However, France had begun to feel that this security was being undermined within a year of its signing. The USA did not ratify the treaty and signed a separate peace with Germany. In Germany, the political situation seemed unlikely to produce a government keen to comply with its terms. Indeed, reparation payments, crucial for rebuilding the French economy, quickly became a problem. The Germans protested that they could not afford the payments. In October 1921, the Wiesbaden Accords were drawn up, by which France agreed to assist Germany with their reparations by taking a proportion in raw materials and industrial produce rather than cash. The following year, however, even these payments had fallen into arrears.

The French inclination to use force rather than diplomacy to resolve the issue was enhanced by the appointment of Raymond Poincaré as Prime Minister in January 1922. The issue was brought to a head and became a crisis when Germany asked for reparation payments to be suspended for four years. The French had had enough. They believed that this suspension could jeopardise the enforcement of the treaty as a whole. The French and the Belgians, with the support of Italy, moved troops into the Ruhr Valley in January 1923 to in kind what they thought they were owed. The German government of Chancellor Wilhelm Cuno protested that this went against the terms of the Versailles Treaty, and in addition instructed Germany workers to strike. The German government continued to pay the now-striking workers, but found it had to print more paper money to cover the bill.

The floundering Germany economy now collapsed, and as the government continued to print money, inflation became hyper-inflation. The French retaliated to this 'passive resistance' by encouraging the unemployed in France and Belgium to work in the Ruhr industries. The descent into economic chaos, indicated by the statistics to the right, coupled with growing political separatist movements in Germany, led to the replacement of Cuno with Gustav Stresemann in August 1923.

Stresemann called for an end to the 'passive resistance' in the Ruhr, and in 1924 the crisis was ended by the Dawes Plan. The plan was named after the commission chaired by the US economist Charles Dawes. He produced a report on German reparations in April 1924, which decided the following:


 * Reparations were to be guaranteed by two mortgages, one on German railways and the second on German industries (supplemented by taxation on the German population),
 * A US 'reparations agent' would reside in Germany to supervise repayments, and
 * Repayments were to be reduced.

Although reparations were to be reduced, France nevertheless accepted the plan because it brought the Americans back into the picture, involving them in the collection of reparations. In fact, this became known as 'the golden age of reparations' (until 1929), as the Allies received more than they had done before. The Germans were unhappy, however, as there was no fixed date for completion of reparations. Britain and France were also concerned about the link between German payments and their own payments of war debts to the USA, which they had not wanted.

The Dawes Plan devised a new system of reparation payments. Stresemann promised to comply with these payments, and French troops were withdrawn from the Ruhr by August 1925. Yet the crisis had thrown up serious problems with the integrity of the League of Nations. Instead of going to the League, France had taken matters into its own hands and attempted to seize payments with force. Indeed, attempts by Britain and Sweden to take the crisis to the League were blocked by the French. This action by a permanent member undermined the League's credibility, as it appeared that the powers would take independent actions when it suited them.

Although the hostility of Britain (and the USA) to the invasion of the Ruhr could be seen as a clear condemnation of unilateral action, the overall impact of the invasion was bad for both the League and for international relations. Despite France's economic gains (it had been guaranteed 21 per cent of the Ruhr's production until December 1923, and then it rose to 27 per cent), the results of its actions dramatically increased the tension between France and Germany, making future cooperation all the more problematic. Politically, France had alarmed its former allies, and heightened the sense of patriotism within Germany. In France, Poincaré came under heavy criticism from both left- and right-wing groups. The left argued that this act of aggression had been committed only to benefit capitalist groups in France, and the right were frustrated by Poincaré’s withdrawal from the Ruhr, seeing it as a missed opportunity to exert some real control over Germany's economy. There were even unofficial support from certain elements for the promotion of an independent Rhineland.

The Rapallo Treaty
In April 1922, the Germans and Russians signed the Rapallo Treaty. By this treaty, Germany and Russia introduced diplomatic relations and pledged their future cooperation. Germany fully recognized the Soviet government and both powers denounced reparations. In addition, the Rapallo Treaty provided for close economic cooperation. Arguably a more important consequence of this treaty was the military cooperation would now take place, allowing Germany to rearm and train secretly in Russia. Knowledge of the Rapallo Treaty also made Britain more determined to win over Germany rather than alienate the nation further, lest Germany became even friendlier with Russia.

The Locarno era
Following the disastrous Ruhr adventure, the political situation in Europe was improved with the Dawes Plan and also the Locarno Pact of 1925, the Kellogg–Briand Pact of August 1928, and the Young Plan of 1929. However, it should be noted that these agreements took place outside of the League of Nations.

The Locarno Conference and the 'Locarno spirit' (1925)
Although French forces left the Ruhr, there were allied troops in other Rhineland cities, as dictated by the terms of Versailles. Stresemann wanted to rid Germany of these 'occupying forces', and he was also keen to quell any movement in support of an independent Rhineland. At a conference in Locarno in Switzerland in February 1925, Stresemann proposed a voluntary German guarantee of its western borders. Significantly for the French and Belgians, this meant that Germany was resolved to give up its claims over Alsace-Lorraine, Malmedy, and Eupen. In return, Germany had some reassurance that France would not invade again, and it moved any potential for an independent Rhineland. A series of treaties were signed. The major treaty guaranteed these boundaries between France, Belgium, and Germany. Also present at Locarno were representatives of Italy, Czechoslovakia, and Poland. Germany signed treaties with Poland and Czechoslovakia, agreeing to change the eastern borders with these countries by arbitration only. It also agreed that Germany should be admitted into the League of Nations.

For many in post-war Europe, the Locarno agreement gave hope for future security. It suggested that former enemies could work together to resolve disputes, and uphold the Versailles settlement. The new mood became known as the 'Locarno spirit'. When Locarno was followed up with a series of agreements involving the USA, this 'spirit' seemed to be embracing even isolationist nations.

The Locarno Pact seemed to bode well for the future of collective security. However, although this agreement appeared to herald a new era of cooperation between the Western European powers (Britain had been in favour of the agreement, as it expunged French excuses for occupation), what the agreement did not guarantee were Germany's eastern borders, and the border with Italy. Italy, present at Locarno, had not managed to get similar agreements from Germany on its southern border. The treaties France had with Poland and Czechoslovakia were little comfort to those respective countries, as it would be strategically difficult to offer tangible support following Locarno. In addition, France had not changed its view of Germany. Rather, it had just changed its strategy for containing Germany. Instead of confronting the Germans with force, France was now attempting to bring Germany into international agreements that involved the guarantees of other powers. In addition, Locarno had undermined both the Treaty of Versailles and the League of Nations. Security for France had been sought outside the League, and only a component of the Versailles Treaty had been guaranteed.

The Young Plan (1929)
The Young Plan attempted to redress some of the problems that remained with the Dawes Plan. The plan:


 * Further reduced the total sum to be repaid by Germany,
 * Set a date for completion of repayments – 1988, and
 * Continued US involvement in reparation payments.

As part of the deal, Britain and France agreed to end their occupation of the Rhineland five years ahead of schedule.

As Keynes had noted in 1926, the foundations for both the Dawes and the Young Plan, and thus both Germany and European recovery, was foreign money. Two-thirds of investment in Germany during the 1920s came from America. Keynes wrote in 1926 that the reparation agreements were 'in the hands of the American capitalists'.

Kellogg–Briand Pact (1928)
The Kellogg–Briand Pact was initiated by American Secretary of State William Kellogg and the French Foreign Minister Aristide Briand. The pact renounced 'war as an instrument of national policy'; 62 of 64 invited states signed the agreement (Brazil and Argentina declined).

Contemporary views of the pact were often positive; it was seen as an important declaration by governments that they would pursue their objectives through peaceful means. The pact has been viewed as the high point of 'Locarno spirit' era. Unfortunately, this perspective would prove to be naive, as the encouraging elements of Europe's recovery were very fragile.

It could be argued that there was no major conflict in the 1920s because the main revisionist power, i.e. Germany, was still recovering from World War I. In addition, the 1920s were in the main period of relative economic boom and prosperity, which decreased international tensions and encouraged cooperation. As P. M. H. Bell writes, 'Europe had survived, but was still on the sick list.'

Why did collective security fail in the 1930s
Although the concept of collective security had some degree of success in the 1920s, the League's failure to resolve key international crises in the 1930s meant that it had completely collapsed by 1939.

The Depression
The worldwide economic depression that followed the Wall Street Crash of October 1929 had far-reaching effects. The USA had become the globally dominant economic power, and this meant that the world's economy was ominously linked to its fortunes. The impact of the crisis on the economic, social, and ultimately political landscape of the world ushered in a return to a world dominated by national self-interest and the dominance of military forces. The USA's national income fell by almost 50 per cent between 1929 and 1932, and its government struggled to cope with unemployment and popular discontent.

Poverty and despair have often fostered the rise of extremist groups, and the fragile liberal governments of the 1920s found resurgent nationalist and aggressive political groups very difficult to restrict. The delicate European stability that had been nurtured by the resources of American capitalism was particularly vulnerable to a major economic collapse in the USA. This was equally true of the recently democratic and liberal China.

Governments were blamed for this crisis. In France, a moderate government was replaced by a radical left-wing government in the May 1932 election. In Britain, iron and steel production fell by 50 per cent and politics shifted to right-wing parties (the British Labour Party lost seats in the 1931 elections). Germany had borrowed £9,000 million between 1924 and 1929. When the money stopped, its economy collapsed; German unemployment stood at 1.4 million in 1928 and rose to a staggering 12 million in 1932. The Weimar government and liberal democracy lost credibility and ended when Franz von Papen assumed the role of virtual dictator in May 1932. In Japan in 1931, 50 per cent of factories closed and silk prices fell by two-thirds. There ensued a radical shift to the right, linked to military factions. By 1932, following a series of assassinations, the era of liberal politics in Japan was now over. In Belgium and Poland, the impact of the Depression led to new government initiatives that looked to improve the countries' defenses against a potentially expansionist Germany.

The responses to the Depression by the democratic states seemed to lead back to an old-style diplomacy, e.g. alliances and agreements outside of the League. The strategy of appeasing countries in response to aggression became more realistic. Economic sanctions were not palatable and to take on aggressors by force was not, at least in the early 1930s when the Depression was tightening its grip, a viable option.

The Manchurian Crisis
Japan was the only independent Asian power with its own empire – an empire that had expanded in 1920 when Japan took over the Mariana and Caroline Islands as mandates. Japan was also Asia's greatest industrial and trading power, and so was badly affected by world depression. Some sections of Japanese society believed that the key to Japan's future economic survival was to expand its empire. However, Asia was already dominated by the European colonial powers; Britain, France, and the Netherlands. They would not tolerate any threat to their interests in the region. In addition, the USA was attempting to increase its influence in the Pacific and would be concerned with any 'aggressive' expansionism there.

In September 1931, the Japanese army in Manchuria, the Kwantung Army (responsible for protecting Japanese interests in the area), claimed that a bomb explosion near the town of Mukdem was evidence of growing disorder, and used it as an excuse to conquer the province. In reality, the Japanese forces had planted the bomb, evidence of the Kwantung Army's desire to expand its influence in the territory.

In this incident, one key member of the League had attacked another member, China. China appealed to the League for assistance against an aggressor; here was exactly the type of incident that 'collective security' was designed to contain. The League of Nations took the following actions:


 * It condemned Japan's actions and ordered the withdrawal of Japanese troops. The Japanese government agreed, but their army refused. This outcome exposed the lack of control the Japanese civilian government had over its military,
 * It appointed a commission under Lord Lytton to investigate the crisis. The commission took more than a year to report, by which time the invasion and the occupation was complete. The commission found Japan guilty of forcibly seizing part of China's territory, and
 * It accepted the Lytton Report and instructed all of its members not to recognise the new Japanese state called Manchukuo. It invited Japan to hand Manchuria back to China.

In response, the Japanese said that they were leaving the League. They claimed that the condemnation of their actions in China was hypocrisy by powers such as Britain, which had a long legacy of using force to achieve its objectives in China. They may have had a point, but the new ideas embodied by the League represented a shift in international tolerance of this kind of empire-building behaviour.

Why did the League fail to resolve the Manchurian Crisis?
There are several reasons that contributed to the League's failure to resolve the crisis:


 * The impact of the Great Depression caused the member states to be too preoccupied with their own troubled domestic situations. It also made them unwilling to apply economic sanctions. In any case, Japan's main trading links were with the USA, which was not a member of the League,
 * Imposing any kind of military solution was problematic, as Manchuria was geographically remote and only Britain and the USA had the naval resources to confront Japan; again the USA was unwilling to do this. Britain was unwilling to act alone and also did not want to risk a naval conflict in the region, where they might well be outnumbered by the Japanese and risk threatening their colonial interest, and
 * France and Italy were too occupied with the events in Europe and were not prepared to agree to any kind of military or naval action against Japan. Again, as with Britain, France's colonial interests in the region made for a confused response. Japan was openly condemned, but privately the government sent a note suggesting that it was sympathetic to the 'difficulties' Japan was experiencing.

What was the impact of the Manchurian Crisis on the League of Nations?
The outcome of the Manchurian Crisis was a dire failure for the League. China had appealed to the League for help in the face of an aggressor, but had received no practical support, neither military nor in terms of economic sanctions. The moral high ground offered by the Lytton Report's verdict was little comfort. The whole affair had suggested that the League lacked the will to follow through with its philosophy of 'collective security'. The aggressor had 'got away with it'. Richard Overy points out that by leaving the League of Nations, Japan had 'effectively remove the Far East from the system of collective security.' In Europe, meanwhile, Mussolini began planning his expansionist adventure into Abyssinia, encouraged by what had happened in Manchuria.

What was the impact of the Manchurian Crisis on the growth of Japanese militarism?
Traditionally, historians have seen the events in Manchuria as the starting point for the dominance of militarism within the Japanese government, which led ultimately to the Pacific war. Some historians, however, view the Manchurian Crisis as less significant to future events in Asia. In The Manchurian Crisis and Japanese Society, 1931–33, Sandra Wilson argues that the crisis had a more limited impact on Japanese thinking than has been suggested. Wilson argues that most Japanese regarded the end of fighting in Manchuria in 1933 as a return to normality, rather than the beginning of the militarisation of Japanese society. Many people in Japanese society even believed that Japan would continue working cooperatively and diplomatically with Britain and the USA. She contends that the post-World War II idea of a 15-year war beginning in the Pacific in 1931 had affected our perception of the Manchurian incident.