World War II (1939–1945)

World War II did not start suddenly. Its roots go back to World War I. After WWI, Germany was punished harshly by the Treaty of Versailles, which caused economic collapse, humiliation, and anger. At the same time, many countries were suffering from the Great Depression, leading people to support extreme political movements that promised order and national pride.

In Germany, Adolf Hitler rose to power, promoting aggressive nationalism and expansion. Similar militaristic governments emerged in Italy and Japan.

These regimes believed they had the right to expand their territory and power by force.

The war officially began in September 1939, when Germany invaded Poland. Britain and France, who had promised to protect Poland, declared war on Germany. Soon after, the conflict spread rapidly across Europe, North Africa, and Asia.

Japan was already fighting in China and later attacked Pearl Harbour in 1941, bringing the United States into the war.

The entire economy and population were mobilized. Industrialized weapons: tanks, aircraft, submarines, and advanced artillery. Civilian involvement: cities were bombed, and civilians were no longer spared.

Nazi Germany carried out the Holocaust, systematically murdering millions of Jews and other targeted groups, creating a horrific genocide.

This war was fought on multiple continents, involved over 100 million soldiers, and affected nearly every major nation.

The war ended when Germany surrendered in May 1945 after being defeated by Allied forces from both the west and the east. Japan surrendered in August 1945 after devastating attacks and the dropping of two atomic bombs.

70–85 million deaths, Europe left in ruins. The United Nations was created. The world entered the Cold War between the U.S. and the Soviet Union.

World War II reshaped global politics, borders, and international law more than any other conflict in history.