IB History · 12 free flashcards

Causes and effects of 20th-century wars flashcards

The key ideas of causes and effects of 20th-century wars for IB History, as flashcards you can study with spaced repetition.

What you need to know

Students must understand the origins, nature, and consequences of major twentieth-century wars, including both world wars, the Spanish Civil War, and regional conflicts. Causes are typically analysed across political, economic, ideological, and military dimensions, with attention to both long-term structural factors and short-term triggers. The role of individuals, nationalism, imperialism, and the failure of international diplomacy all feature prominently. Effects are examined across political, social, and economic spheres, including territorial changes, civilian casualties, shifts in power, and the emergence of new ideologies or regimes. Students should be able to construct analytical arguments that weigh causes against one another and assess the significance of consequences, avoiding oversimplification and demonstrating awareness of historiographical debate where relevant.

Causes and effects of 20th-century wars: 12 key flashcards

  1. Card 1

    What is the difference between a long-term cause and a short-term trigger in war?

    A long-term cause builds over years (e.g. imperial rivalry), while a short-term trigger is an immediate event that sparks conflict, such as an assassination or ultimatum.
  2. Card 2

    How did nationalism contribute to the outbreak of the First World War?

    Nationalism intensified rivalries between European powers and fuelled movements like Pan-Slavism, destabilising the Austro-Hungarian Empire and increasing the likelihood of armed conflict.
  3. Card 3

    What role did the alliance system play in escalating the First World War?

    The alliance system turned a localised Austro-Serbian dispute into a continental war, as treaty obligations drew Germany, Russia, France, and Britain into the conflict rapidly.
  4. Card 4

    What is meant by 'total war' and why is it significant?

    Total war involves the mobilisation of an entire nation's resources, economy, and population for the war effort, blurring the distinction between soldiers and civilians.
  5. Card 5

    How did the Treaty of Versailles contribute to the causes of the Second World War?

    The Treaty of Versailles imposed harsh reparations and territorial losses on Germany, creating economic hardship and nationalist resentment that Hitler exploited to gain power.
  6. Card 6

    What is appeasement and how did it affect the lead-up to the Second World War?

    Appeasement was the policy of making concessions to aggressive powers to avoid war. It emboldened Hitler, as seen at Munich in 1938, and delayed but failed to prevent conflict.
  7. Card 7

    What were the main ideological causes of the Spanish Civil War?

    The war arose from clashes between fascism and republicanism/communism, with Franco's Nationalists backed by Hitler and Mussolini against the left-wing Popular Front government.
  8. Card 8

    How did the Second World War affect the global balance of power?

    The war led to the decline of European empires and the rise of two superpowers, the USA and USSR, whose ideological rivalry shaped the Cold War era that followed.
  9. Card 9

    What is the significance of economic factors as a cause of twentieth-century wars?

    Economic factors such as competition for markets, resources, and colonies drove imperial rivalry before 1914, and the Great Depression destabilised democracies, aiding the rise of fascism.
  10. Card 10

    What were the main social effects of the First World War on European societies?

    The war caused mass casualties, disrupted gender roles as women entered the workforce, and contributed to social upheaval including revolutions in Russia and Germany.
  11. Card 11

    How did militarism contribute to the outbreak of the First World War?

    Militarism led to an arms race, particularly between Britain and Germany in naval power, increasing mutual suspicion and making military solutions to disputes more likely.
  12. Card 12

    Why is it important to consider historiographical debate when analysing causes of war?

    Historians disagree on emphasis; for example, Fischer's thesis blamed German aggression for WWI, while others stress shared responsibility, showing causes are interpreted differently over time.

Quick quiz

Question 1 of 3

Which factor is most closely associated with the concept of 'militarism' as a cause of the First World War?

Common mistakes

  • Students often treat the assassination of Franz Ferdinand as the primary cause of the First World War rather than recognising it as a short-term trigger that ignited pre-existing long-term tensions.
  • Many candidates conflate the effects of the First World War with the causes of the Second, failing to construct a clear analytical distinction between the two conflicts when structuring their essays.
  • A common error is to argue that appeasement was simply a cowardly or foolish policy, without acknowledging the genuine constraints facing British and French leaders, such as public opposition to war and military unpreparedness.

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