World War II was the largest and most devastating military conflict in history, affecting much of the world and changing the course of humanity.

When it happened

• Start: September 1, 1939, with the invasion of Poland by Germany.
• End: September 2, 1945, with Japan's surrender.
• Duration: 6 years and 1 day.

Main causes

1. Treaty of Versailles (1919): The harsh conditions imposed on Germany after World War I created resentment and a desire for revenge.
2. Nazi expansionism: Led by Adolf Hitler, Germany sought to expand territorially under the ideology of Aryan superiority.
3. Fascism and militarism: Countries like Italy and Japan pursued aggressive expansionist policies.
4. Failure of the League of Nations: The League’s inability to prevent smaller conflicts allowed them to escalate into global war.

Countries involved

The countries were divided into two main blocs:

1. The Allies:
   • Main members: United States, United Kingdom, Soviet Union, China, and France (though occupied by Germany in 1940).
   • Other countries: Canada, Australia, India, Brazil, among many others.
2. The Axis Powers:
   • Main members: Germany, Italy, and Japan.
   • Other allies: Hungary, Romania, Bulgaria, and countries occupied by Germany.

Where it was fought

The war was truly global, fought on multiple fronts:

• Europe: Germany and its allies fought against the Allies in France, Russia, Italy, the Balkans, and other territories.
• Pacific: Japan advanced over East Asia and the Pacific, facing the United States, China, and other Allied forces.
• North Africa: Battles between Axis and Allied forces in Egypt, Libya, and other territories.
• Atlantic: Naval battles and Germany's naval blockade.
• Eastern Front: One of the deadliest fronts, primarily between Germany and the Soviet Union.

Estimated deaths

It is estimated that there were:

• Over 70 million deaths, including both military and civilian casualties.
• The majority of civilian victims were from the Soviet Union, China, and Eastern Europe.
• Holocaust: Six million Jews were murdered by the Nazi regime, along with millions of other minorities and prisoners.

Main consequences

1. End of fascism in Europe: Defeat of Germany, Italy, and Japan.
2. New superpowers: The United States and the Soviet Union emerged as the leading world powers, marking the beginning of the Cold War.
3. Creation of the UN (1945): To prevent future conflicts of this scale.
4. Division of Germany: Into zones controlled by the victorious powers, leading to the separation of East and West Germany.
5. Redrawing of borders: Many regions changed hands, and several parts of the world were decolonized in the following decades.

World War II left an indelible mark on history, not only due to its magnitude but also because of the political, social, and economic impact it had in the decades that followed.