* The rise of nationalism and militarism in Europe in the 1930s: After the end of World War I, many European countries were left economically and politically weak. This created a fertile ground for nationalism and militarism to take hold, as people looked to strong leaders to restore their countries to their former glory.
* The Treaty of Versailles: The Treaty of Versailles, which ended World War I, was widely seen as too harsh on Germany. This resentment of the treaty helped to fuel nationalism and militarism in Germany, and made it easier for Adolf Hitler to come to power.
* The Manchurian Crisis of 1931: The Japanese invasion of Manchuria in 1931 was a major flashpoint in the lead-up to World War II. The League of Nations failed to condemn the invasion, which emboldened Japan and other aggressive powers.
* The rise of Adolf Hitler and Nazism in Germany: Hitler came to power in Germany in 1933 and quickly began to rearm the country and pursue an aggressive foreign policy. Hitler's actions, such as the remilitarization of the Rhineland in 1936 and the annexation of Austria in 1938, made it clear that he was willing to use force to achieve his goals.
* The appeasement policies of the Western powers: The Western powers, including Britain, France, and the United States, were reluctant to go to war with Germany over its aggressive actions in the 1930s. This policy of appeasement only emboldened Hitler and made it easier for him to start World War II.
Overall, it is clear that there were a number of factors that contributed to the outbreak of World War II. These factors included the rise of nationalism and militarism in Europe, the Treaty of Versailles, the Manchurian Crisis of 1931, and the rise of Hitler and Nazism in Germany. The Western powers' appeasement policies also played a role in making it easier for Hitler to start the war.