AP World Unit 7 Review: Global Conflicts (1900-Present)

At the start of the twentieth century, Western powers dominated global politics, but land-based empires were already under severe stress. The Ottoman, Russian, and Qing empires each collapsed under a combination of internal weaknesses and external pressures, producing new states and revolutionary governments by the 1920s.

• Ottoman collapse: Military defeats, nationalist movements among subject peoples, and financial dependence on European creditors eroded Ottoman authority, leading to the empire's dissolution after WWI.
• Russian Revolution: Military failure in WWI, food shortages, and worker unrest toppled the tsar in February 1917; the Bolsheviks under Lenin then seized power in October 1917, establishing a communist state.
• 1911 Revolution (Qing): Internal reform failures, foreign pressure, and Han Chinese nationalism overthrew the Qing dynasty and established the Chinese Republic under Sun Yat-sen and the Guomindang.
• Mexican Revolution: Political crisis under Porfirio Diaz sparked a decade of armed conflict beginning in 1910, producing land reform demands and a new constitutional order.
• Western dominance challenged: While Western maritime empires remained strong in 1900, the collapse of land-based empires and the rise of revolutionary states signaled a shift in the global political order that would accelerate through the century.

WWI broke out in 1914 because multiple long-term pressures converged with a short-term trigger. The MANIA framework captures the main causes: Militarism, Alliance system, Nationalism, Imperialism, and Assassination. No single cause is sufficient; the AP exam expects you to weigh their relative significance.

• Alliance system: The Triple Entente (France, Russia, Britain) and Triple Alliance (Germany, Austria-Hungary, Italy) meant a regional dispute could rapidly pull all major powers into war.
• Imperialism and resource competition: European powers competed for colonies and markets, producing crises like the Moroccan Crises that heightened tensions before 1914.
• Nationalism: Pan-Slavism in the Balkans and German nationalism intensified rivalries; the Black Hand's Serbian nationalism directly motivated the assassination of Archduke Franz Ferdinand.
• Assassination of Franz Ferdinand: Gavrilo Princip killed the Austro-Hungarian heir in Sarajevo on June 28, 1914, triggering the July Crisis and activating the alliance system.
• Militarism: An arms race, especially the Anglo-German naval rivalry, normalized military buildup and made war seem like a viable policy tool.

WWI introduced the concept of total war: governments mobilized entire societies, including colonial populations, to sustain the conflict. Propaganda, censorship, conscription, and war bonds kept home fronts committed. New military technology made the war far deadlier than any previous conflict.

• Total war: Governments directed economies, labor, and civilian life toward the war effort, blurring the line between soldiers and civilians.
• Propaganda: Governments used posters, film, and media to build nationalist support, recruit soldiers, and dehumanize enemies in both home countries and colonies.
• Colonial mobilization: Britain, France, and other empires recruited soldiers and laborers from colonies in Africa, South Asia, and Southeast Asia, raising expectations of postwar political recognition.
• New military technology: Machine guns, poison gas, tanks, and aircraft produced trench stalemate on the Western Front and drove casualties at battles like the Somme and Verdun to catastrophic levels.
• Fourteen Points: Woodrow Wilson's 1918 peace framework emphasized self-determination, free trade, and a League of Nations, shaping postwar negotiations and raising hopes that were only partially fulfilled.

The Great Depression beginning in 1929 forced governments worldwide to abandon laissez-faire economics and intervene directly in their economies. Different political systems responded in very different ways, but all expanded state power over economic life.

• Great Depression: The 1929 stock market crash triggered a global economic collapse, causing mass unemployment, deflation, and political instability that weakened democratic governments and strengthened extremist movements.
• New Deal: FDR's US program used government spending, regulation, and social welfare programs to provide relief and recovery, expanding the federal government's economic role.
• Five Year Plans: Stalin's Soviet Union used centralized state planning to rapidly industrialize, collectivizing agriculture and repressing dissent, with severe human costs including famine.
• Fascist corporatist economy: Italy under Mussolini and Germany under Hitler used state-directed corporatism, controlling industry and labor while maintaining nominal private ownership to mobilize economies for nationalist goals.
• Brazil and Mexico: Governments with strong popular support, such as Vargas in Brazil and Cardenas in Mexico, used economic nationalism and state intervention to manage the Depression's impact and build domestic industries.

The post-WWI settlement did not dismantle Western or Japanese empires. Colonial peoples who had supported the war effort found their demands for self-determination ignored. New territorial arrangements through League of Nations mandates extended imperial control under a different name, while anti-imperial resistance grew.

• League of Nations mandates: Former German colonies were transferred to Britain and France as mandates, maintaining imperial control while framing it as temporary trusteeship toward self-governance.
• Manchukuo: Japan established this puppet state in Manchuria in 1932, part of its Greater East Asia Co-Prosperity Sphere strategy to control resources and markets across Asia.
• Indian National Congress: Led by figures including Mohandas Gandhi, the INC organized mass resistance to British rule through nonviolent campaigns, growing in strength during the interwar period.
• West African resistance: Strikes and congresses in French West Africa challenged colonial labor policies and political exclusion, representing organized anti-imperial resistance outside South Asia.
• Continuity and change: The key AP skill for 7.5 is recognizing that imperial control largely continued after WWI (continuity) while anti-imperial resistance intensified (change), setting up decolonization after WWII.

WWII grew directly from WWI's unresolved problems. The unsustainable Versailles settlement, the Great Depression, continued imperial ambitions, and the rise of fascist regimes combined to produce a second global conflict. Like WWI, WWII was a total war, but ideology played a more explicit role in mobilization and repression.

• Causes of WWII: The four main causes were the flawed Versailles peace, the Great Depression, continued imperialism, and the aggressive militarism of fascist regimes, especially Nazi Germany under Hitler.
• Fascism and totalitarianism: Nazi Germany and Fascist Italy used state ideology to mobilize populations, suppress opposition, and justify territorial expansion; the Munich Agreement showed Western powers initially appeasing Hitler.
• Total war in WWII: Governments again mobilized entire economies and populations; democracies like Britain under Churchill and the US under FDR used propaganda and conscription, while totalitarian states also used ideology to repress freedoms.
• New military technology: Blitzkrieg tactics, firebombing of civilian cities, and ultimately the atomic bombs dropped on Hiroshima and Nagasaki pushed WWII casualties far beyond WWI levels.
• Atomic bomb: The US use of atomic weapons against Japan in August 1945 ended the Pacific war and introduced nuclear weapons as a permanent feature of global power politics.

Extremist regimes and ethnic nationalist movements produced systematic mass killings across the twentieth century. The AP exam expects you to know multiple cases, explain their causes, and understand their consequences for international law and human rights norms.

• Holocaust: The Nazi regime systematically murdered six million Jews and millions of others through concentration camps, mass shootings, and gas chambers; the Nuremberg Trials established individual accountability for crimes against humanity.
• Armenian Genocide: The Ottoman government deported and killed approximately 1.5 million Armenians during and after WWI, making it one of the first modern genocides.
• Holodomor: Stalin's forced collectivization and grain confiscation policies caused a man-made famine in Soviet Ukraine from 1932 to 1933, killing millions of Ukrainians.
• Cambodian Genocide: The Khmer Rouge under Pol Pot killed approximately 1.7 million people from 1975 to 1979, targeting intellectuals, ethnic minorities, and perceived class enemies.
• Rwandan Genocide: In 1994, Hutu extremists killed approximately 800,000 Tutsi and moderate Hutu in roughly 100 days, exposing the limits of international intervention and the UN's capacity to prevent genocide.

Topic 7.9 is a synthesis skill topic, not a new content block. It asks you to rank and explain the relative significance of causes of global conflict from 1900 to the present. You are connecting militarism, alliances, imperialism, nationalism, economic crisis, and unresolved tensions into a defensible argument about which mattered most and why.

• Relative significance: The AP skill of explaining which cause was most important requires you to compare causes, not just list them; you need evidence that one factor had broader or deeper effects than others.
• Technology as a cause: Rapid advances in military technology, from machine guns to atomic bombs, changed the scale and nature of conflict and made wars more destructive, amplifying other causes.
• Nationalism and ideology: Across WWI, WWII, and mass atrocities, nationalist and ideological extremism repeatedly transformed political tensions into mass violence.
• Economic instability: The Great Depression destabilized democratic governments and created conditions for fascist and authoritarian movements to gain power, linking economic crisis directly to WWII's causes.
• Continuity across conflicts: Unresolved tensions from WWI directly caused WWII; patterns of imperial control, nationalist resistance, and ideological competition continued across the entire 1900-present period.