World War II: Causes, Key Events, and Consequences

The Stalinist totalitarian state's territorial expansion, along with German, Italian, and Japanese expansionism, and the anti-Comintern pact, provoked the rupture of democratic nations (Britain and France). The implementation of a policy of appeasement and the formation of the Axis (Berlin-Rome-Tokyo) through cooperation agreements in 1936 set the stage for conflict. Germany invaded Poland in September 1939, triggering the war.

The War's Phases

Phase 1

Germany quickly conquered Denmark, Norway, the Netherlands, Belgium, and France using blitzkrieg tactics. Hitler's attempt to invade England failed in the Battle of Britain. Germany then pressured Romania, Bulgaria, Hungary, and Slovakia to join the Axis. In 1941, Germany invaded Yugoslavia and Greece, taking control of the Balkans. Hitler then turned his attention to the USSR.

Phase 2

The USSR, initially neutral, became an ally of Britain. The Japanese bombing of Pearl Harbor in 1941 forced the U.S. into the war. In most countries occupied by the Germans and Japanese, resistance movements fought underground against the invaders, using sabotage and street fighting. The Japanese invasion of Southeast Asia in 1942 led to the detention of Allied forces. Leaders like Churchill, Roosevelt, and Stalin coordinated offensives at conferences like the 1943 Tehran Conference and the 1945 Yalta Conference.

Phase 3

The Axis powers began to collapse. Germany and Italy were defeated in Africa, leading to the fall of Italian fascism. The German defeat in the Battle of Stalingrad marked a turning point, enabling the liberation of Russia. In June 1944, the Allied landing in Normandy facilitated the liberation of Western Europe. The Russians advanced on Germany in April 1945, and Hitler died in Berlin. Germany surrendered in May 1945. The Japanese Empire in the Pacific resisted fiercely. The U.S. launched two atomic bombs on Hiroshima and Nagasaki, leading to Japan's surrender in September 1945.

Demographic and International Consequences

• More than 50 million people died, including Jews and Gypsies in the Nazi genocide.
• The power of European nations diminished, while the United States and the Soviet Union rose to prominence.
• The Yalta and Potsdam conferences divided Europe into Eastern Europe (under Soviet military occupation) and Western Europe (under U.S. protection).
• Germany lost territory and was occupied by Russian, British, French, and U.S. forces.
• Japan was militarily occupied and imposed a democratic system.
• European economies were devastated by bombing, except for the U.S., which contributed to the reconstruction of Europe through the Marshall Plan.

Key Post-War Conferences

• Yalta (USSR, 1945): Discussed war strategy and decided to create a world organization to end armed conflicts.
• San Francisco (USA, 1945): Established the United Nations.
• Potsdam (Germany, 1945): Agreed to the total disarmament and denazification of Germany, as well as the division of its territory into four zones.