1. Treaty of Versailles and Rise of Nationalism: The harsh terms imposed on Germany after World War I, as outlined in the Treaty of Versailles, created widespread resentment and a desire for revenge among many Germans. Adolf Hitler's Nazi party capitalized on this sentiment and promised to restore Germany's greatness.
2. German Expansionism: Hitler pursued an aggressive policy of territorial expansion, beginning with the remilitarization of the Rhineland in 1936 and the annexation of Austria in March 1938. These actions violated the Treaty of Versailles and were largely unopposed by other European powers.
3. Appeasement Policy: The Western Allies, including Britain and France, initially adopted a policy of appeasement towards Germany, hoping to avoid another war. They agreed to Hitler's demands in the Munich Agreement of September 1938, which allowed Germany to annex the Sudetenland region of Czechoslovakia. However, this appeasement only emboldened Hitler.
4. Failure of the League of Nations: The League of Nations, established after World War I to prevent future conflicts, failed to effectively deter Germany's aggression. The League was unable to enforce its resolutions or take collective action against Germany, largely due to the reluctance of some of its members to go to war.
5. Poland and Danzig Crisis: Hitler's next territorial demand was for the city of Danzig (Gdansk), which had a predominantly German population but was part of Poland. Poland refused to give in to these demands, and on September 1, 1939, Germany invaded Poland, triggering the declaration of war by Britain and France.
6. Non-Aggression Pact and Molotov-Ribbentrop Pact: In August 1939, Germany and the Soviet Union signed the non-aggression pact known as the Molotov-Ribbentrop Pact. This agreement allowed Germany to focus on its western front while ensuring Soviet neutrality. It also included secret protocols dividing Poland and other parts of Eastern Europe between Germany and the Soviet Union.
7. Outbreak of War: The German invasion of Poland on September 1, 1939, was a direct violation of the non-aggression pact with Poland and led to Britain and France declaring war on Germany on September 3, marking the official start of World War II.
It's important to note that the outbreak of World War II was the result of a complex combination of historical, political, economic, and social factors, and this simplified explanation focuses on the immediate events leading to the conflict.