Unit 8: 20th-Century Global Conflicts
AP European History: 29 practice questions with detailed explanations.
Unit Study Guide
Executive Summary
Two world wars and the genocides between them remade Europe. Alliances, total war, and ideological extremism are the through-lines.
World War I (1914-1918)
Long-term causes: nationalism, militarism, alliances (Triple Entente vs Triple Alliance), imperial rivalry. Spark: assassination of Franz Ferdinand at Sarajevo. The Schlieffen Plan failed; the Western Front froze into trench warfare with new weapons (machine guns, poison gas, tanks). Total war mobilized whole societies; propaganda sustained morale. The US entered in 1917. The Treaty of Versailles blamed Germany, imposed reparations, and created the League of Nations.
The Russian Revolution
War collapse toppled Tsar Nicholas II (March 1917). Lenin's Bolsheviks seized power in October; Brest-Litovsk took Russia out of the war; the Red-White civil war produced the Soviet Union (1922).
The interwar crisis
The Weimar Republic faced hyperinflation and political violence; the Great Depression (1929) fueled extremism. Mussolini's Fascists took Italy (1922); Hitler became chancellor (1933). Stalin's five-year plans, collectivization, and the Great Purge transformed the USSR at horrific cost.
World War II (1939-1945)
Appeasement at Munich (1938) emboldened Hitler; the Nazi-Soviet Pact preceded the invasion of Poland. Blitzkrieg crushed France (1940); the Battle of Britain failed; Operation Barbarossa (1941) stalled at Stalingrad; D-Day (1944) opened the west; Germany surrendered in May 1945.
The Holocaust
Systematic genocide of six million Jews: Nuremberg Laws, ghettos, Einsatzgruppen, and extermination camps (Auschwitz-Birkenau), coordinated at Wannsee (1942). The Nuremberg Trials prosecuted the perpetrators.
Exam traps
The war guilt clause singled out Germany — a later grievance, not a full historical account. The Holocaust was industrial and systematic, not wartime chaos.