In simple terms
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War: The Why and the What Next
This topic explores why major conflicts started in the 20th century and what changed as a result. We learn to dissect wars like a detective, looking for clues in the long-term tensions, immediate triggers, and the widespread aftermath.
Think of a massive falling out in a friendship group. The 'long-term causes' are the small, underlying annoyances and personality clashes that have been building for months. The 'short-term cause' might be a specific argument over plans last week. The 'immediate trigger' is one person saying something harsh that starts the huge fight. The 'effects' are how the group dynamic changes afterwards: some people stop talking (political/social), someone has to pay for a broken object (economic), and the whole atmosphere is different (social).
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Identify the War's Nature: First, classify the conflict. Is it a total war involving entire nations (like WWII), a civil war within one country (like the Spanish Civil War), or a guerrilla conflict?
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Categorise the Causes: Break down the origins of the war. Separate them into long-term factors (e.g., imperialism, nationalism), short-term crises (e.g., the July Crisis of 1914), and the immediate trigger (e.g., the assassination of Archduke Franz Ferdinand).
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Analyse the Effects Systematically: Examine the consequences across four key areas. What were the economic impacts (debt, destruction), social changes (role of women, class structures), political shifts (new governments, collapsed empires), and demographic outcomes (casualties, refugees)?
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Synthesise and Evaluate: For top marks, connect the causes to the effects and form a judgement. Argue which causes were most significant or which effects were most transformative, supporting your claims with specific evidence and considering different historical interpretations.
Explore the concept
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Key formulas
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Full topic notes
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Understanding the 'Types' of War
Before analysing causes and effects, you must first identify the nature of the conflict. The type of war often dictates its scale, methods, and consequences. For Paper 2, you will compare wars from different regions, and their types might be a key point of comparison or contrast.
Total War: Mobilises all of a state's resources, including its economy and population, towards the war effort. Often features a blurring of the lines between combatants and civilians. (e.g., World War I, World War II).
Civil War: A conflict fought between factions within the same country. The struggle is for national control or regional secession. (e.g., Spanish Civil War, Chinese Civil War).
Guerrilla War: An asymmetrical conflict where a smaller, more mobile force uses unconventional tactics against a larger, conventional military. Often overlaps with civil wars or wars of independence. (e.g., Vietnam War, Mao's forces in the Chinese Civil War).
Limited War: A conflict where the objectives, means, and geographical scope are restricted, falling short of a total war. (e.g., Korean War, Falklands War).
Deconstructing the Causes of War
Examiners look for a structured analysis of causation, not just a list of reasons. A powerful analytical tool is to categorise causes by timeframe (long-term, short-term, immediate) and by theme (economic, ideological, political). This structure helps you build a multi-faceted argument and evaluate the relative importance of different factors.
Analytical Framework: (Long-term + Short-term + Immediate Causes) x (Economic + Ideological + Political Factors) = Comprehensive Analysis
Analysing the Effects of War
Similar to causes, a thematic approach is essential for analysing effects. Categorise the consequences of war into political, economic, social, and demographic impacts. High-scoring answers will also consider the varying effects on different groups within a society (e.g., women, ethnic minorities, social classes) and distinguish between short-term and long-term consequences.
Worked examples
See the formulas applied — reveal one step at a time, like the exam.
Analyse the role of economic and ideological factors in causing two 20th-century wars, each from a different region.
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This question requires a comparative analysis of causes for two wars, focusing on economic and ideological factors. Let's choose the First World War (1914-1918) and the Vietnam War (US involvement from 1965).
Evaluate the social and economic effects of the Second World War on one country.
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This question asks for an evaluation of specific effects on one nation. Let's choose Britain.
How it all connects
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Glossary
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Quick check
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Revision flashcards
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Total War
A war that is unrestricted in terms of the weapons used, the territory or combatants involved, or the objectives pursued. It involves the complete mobilisation of a nation's resources and population. Example: World War II.
Key takeaways
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Total War: Mobilises all of a state's resources, including its economy and population, towards the war effort. Often features a blurring of the lines between combatants and civilians. (e.g., World War I, World War II).
- ✓
Civil War: A conflict fought between factions within the same country. The struggle is for national control or regional secession. (e.g., Spanish Civil War, Chinese Civil War).
- ✓
Guerrilla War: An asymmetrical conflict where a smaller, more mobile force uses unconventional tactics against a larger, conventional military. Often overlaps with civil wars or wars of independence. (e.g., Vietnam War, Mao's forces in the Chinese Civil War).
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Limited War: A conflict where the objectives, means, and geographical scope are restricted, falling short of a total war. (e.g., Korean War, Falklands War).
Practice — then mark it
The whole point: a real Cambridge question, marked mark-by-mark.
Practice Paper 2 Questions on 20th-Century Wars
Practice Paper 2 Questions on 20th-Century Wars
Extra simulations & links
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Frequently asked
Checkpoint
One marked question is worth ten re-reads — close the loop before you move on.
Reading it isn’t knowing it — prove it.
Before you move on: do Practice Paper 2 Questions on 20th-Century Wars on paper, snap a photo, and get examiner-style feedback on exactly where you win and lose marks.