Pearson Baccalaureate – World History:
Causes and Effects of 20th Century Wars
World War II – Causes I: The failure of collective security (p. 99 – 123)
The failure of ‘collective security’
Newly established LoN faced many challenges: Successful in some areas BUT failure of
European states to work collectively through League in dealing with various international
crises → major cause of WWII
Collective security and the League of Nations + The Covenant of the LoN:
Main aims were to keep peace by advising on and settling international disputes. It also
promoted disarmament, international goodwill and cooperation and supervised
mandates. By 1926 all ex-enemy states had joined. (USSR not until 1934 and USA never joined)
Dealing with international disputes:
If member states failed to refer their international disputes to the League, the League could
impose military sanctions. As a last resort against an aggressor the League could call for military
action (even though it didn’t possess an own military).
Problems for the LoN in the 1920s
Changing membership of the League:
Liberal governments became increasingly polarized and right-wing governments became more
aggressive (USSR).
Absence of major powers:
→ key reason why the League failed to prevent another war.
Most important absent major power was the USA. US Congress was too concerned that the
membership would drag America into European conflicts and therefore withdrew to US
isolationism. The absence of the USA seriously weakened the LoN because:
o World’s strongest economy would’ve given the sanctions real weight.
o LoN lacked appearance of worldwide organization
→ LoN was primarily led by European powers which were in DECLINE
Absence of the USSR:
Afraid that the ‘revolution of the proletariat’ would spread the old powers of Europe isolated the
Soviets. → Lenin viewed LoN as ‘robbers’
Absence of Germany:
Germany was originally excluded, which undermined the ideals of the League.
Additionally, the exclusion tended to ignore that Germany remained a strong power and that
Germany hadn’t been defeated that clearly (particularly in the East).
→ vital that Germany was included so that it could work towards its aim of revising the Treaty
of Versailles (admitted in 1926)
Weakness of Central European states:
, Austro-Hungarian Empire had collapsed and got replaced by much smaller states, which
struggled politically and economically. They would’ve required more support from the League
and couldn’t offer much tangible support in return.
How successful was the League of Nations in the 1920s?
Various disputes arising mainly from territorial changes from the Treaty of Versailles:
Aaland Islands, Upper Silesia, Mosul and Bulgaria: success; Vilna, Corfu: failure.
Attempts to strengthen the League:
Two initiatives: One which would’ve required all members of the League to come to assistance
of a victim of aggression and the other would’ve made the Geneva Protocol of 1924’ arbitration
compulsory in all disputes.
→ both rejected (too much commitment would’ve had been carried out)
League remained divided between states that wanted a strong League to enforce the existing
territorial agreements (usually more vulnerable states) and those wanting to be more selective in
dealing with aggression.
The Ruhr Crisis
Future security of France depended on upholding the terms of Versailles. However, this security
was continuously undermined. Germans couldn’t pay reparations, which were vital for the
rebuilding of France’s economy. France felt like they had to use force to solve this problem and
moved troops into the Ruhr Area in 1923. The German chancellor protested and instructed
German workers in the Ruhr Area to strike while still paying them loans. He then had to
print more paper money to cover the bill.
→ Economy collapsed and inflation turned into hyperinflation
→ France retaliated by ordering French and Belgians to work in the Ruhr industries.
The Americas intervened by ordering the Germans to pay the reparations and controlling them
in doing this. In addition, reparations were reduced. = Dawes Plan
→ French troops were withdrawn
→ Ruhr occupation undermined the League’s credibility and led to hostility of Britain and
the USA but more importantly increased tension between Germany and France
The Rapallo Treaty
Germany and Russia pledged their future cooperation by signing the Rapallo Treaty in 1922.
It included: diplomatic relations, denouncement of reparations, economic cooperation and most
significantly military cooperation, allowing Germany to rearm and secretly train in Russia.
The Locarno Era
The Locarno Conference and the Locarno Spirit (1925)
Germany wanted to get rid of French ‘occupying forces’ and resolved Germany’s claims over
Alsace-Lorraine and other French areas at a conference in Locarno. In return France would not
invade again. Germany also signed treaties with Poland and Czechoslovakia, agreeing not to
change borders with these countries without arbitration. Germany was also to be admitted to the
LoN. → The Locarno Conference gave hope for future security.
However, the agreement did not guarantee Germany’s eastern and southern borders.
→ Locarno had undermined the LoN and the Treaty of Versailles.
Causes and Effects of 20th Century Wars
World War II – Causes I: The failure of collective security (p. 99 – 123)
The failure of ‘collective security’
Newly established LoN faced many challenges: Successful in some areas BUT failure of
European states to work collectively through League in dealing with various international
crises → major cause of WWII
Collective security and the League of Nations + The Covenant of the LoN:
Main aims were to keep peace by advising on and settling international disputes. It also
promoted disarmament, international goodwill and cooperation and supervised
mandates. By 1926 all ex-enemy states had joined. (USSR not until 1934 and USA never joined)
Dealing with international disputes:
If member states failed to refer their international disputes to the League, the League could
impose military sanctions. As a last resort against an aggressor the League could call for military
action (even though it didn’t possess an own military).
Problems for the LoN in the 1920s
Changing membership of the League:
Liberal governments became increasingly polarized and right-wing governments became more
aggressive (USSR).
Absence of major powers:
→ key reason why the League failed to prevent another war.
Most important absent major power was the USA. US Congress was too concerned that the
membership would drag America into European conflicts and therefore withdrew to US
isolationism. The absence of the USA seriously weakened the LoN because:
o World’s strongest economy would’ve given the sanctions real weight.
o LoN lacked appearance of worldwide organization
→ LoN was primarily led by European powers which were in DECLINE
Absence of the USSR:
Afraid that the ‘revolution of the proletariat’ would spread the old powers of Europe isolated the
Soviets. → Lenin viewed LoN as ‘robbers’
Absence of Germany:
Germany was originally excluded, which undermined the ideals of the League.
Additionally, the exclusion tended to ignore that Germany remained a strong power and that
Germany hadn’t been defeated that clearly (particularly in the East).
→ vital that Germany was included so that it could work towards its aim of revising the Treaty
of Versailles (admitted in 1926)
Weakness of Central European states:
, Austro-Hungarian Empire had collapsed and got replaced by much smaller states, which
struggled politically and economically. They would’ve required more support from the League
and couldn’t offer much tangible support in return.
How successful was the League of Nations in the 1920s?
Various disputes arising mainly from territorial changes from the Treaty of Versailles:
Aaland Islands, Upper Silesia, Mosul and Bulgaria: success; Vilna, Corfu: failure.
Attempts to strengthen the League:
Two initiatives: One which would’ve required all members of the League to come to assistance
of a victim of aggression and the other would’ve made the Geneva Protocol of 1924’ arbitration
compulsory in all disputes.
→ both rejected (too much commitment would’ve had been carried out)
League remained divided between states that wanted a strong League to enforce the existing
territorial agreements (usually more vulnerable states) and those wanting to be more selective in
dealing with aggression.
The Ruhr Crisis
Future security of France depended on upholding the terms of Versailles. However, this security
was continuously undermined. Germans couldn’t pay reparations, which were vital for the
rebuilding of France’s economy. France felt like they had to use force to solve this problem and
moved troops into the Ruhr Area in 1923. The German chancellor protested and instructed
German workers in the Ruhr Area to strike while still paying them loans. He then had to
print more paper money to cover the bill.
→ Economy collapsed and inflation turned into hyperinflation
→ France retaliated by ordering French and Belgians to work in the Ruhr industries.
The Americas intervened by ordering the Germans to pay the reparations and controlling them
in doing this. In addition, reparations were reduced. = Dawes Plan
→ French troops were withdrawn
→ Ruhr occupation undermined the League’s credibility and led to hostility of Britain and
the USA but more importantly increased tension between Germany and France
The Rapallo Treaty
Germany and Russia pledged their future cooperation by signing the Rapallo Treaty in 1922.
It included: diplomatic relations, denouncement of reparations, economic cooperation and most
significantly military cooperation, allowing Germany to rearm and secretly train in Russia.
The Locarno Era
The Locarno Conference and the Locarno Spirit (1925)
Germany wanted to get rid of French ‘occupying forces’ and resolved Germany’s claims over
Alsace-Lorraine and other French areas at a conference in Locarno. In return France would not
invade again. Germany also signed treaties with Poland and Czechoslovakia, agreeing not to
change borders with these countries without arbitration. Germany was also to be admitted to the
LoN. → The Locarno Conference gave hope for future security.
However, the agreement did not guarantee Germany’s eastern and southern borders.
→ Locarno had undermined the LoN and the Treaty of Versailles.
