Causes of World War II
The causes of World War II have been given considerable attention by historians. The immediate precipitating event was the invasion of Poland by Nazi Germany on September 1, 1939, and the subsequent declarations of war on Germany made by Britain and France, but many other prior events have been suggested as ultimate causes. Primary themes in historical analysis of the war's origins include the political takeover of Germany in 1933 by Adolf Hitler and the Nazi Party; Japanese militarism against China, which led to the Japanese invasion of Manchuria and the Second Sino-Japanese War; Italian aggression against Ethiopia, which led to the Second Italo-Ethiopian War; or military uprising in Spain, which led to the Spanish Civil War.
During the interwar period, deep anger arose in the Weimar Republic over the conditions of the 1919 Treaty of Versailles, which punished Germany for its role in World War I with heavy financial reparations and severe limitations on its military that were intended to prevent it from becoming a military power again. The demilitarisation of the Rhineland, the prohibition of German unification with Austria, and the loss of its overseas colonies as well as some 12% of the pre-war land area and population of the metropole all provoked strong currents of revanchism in German politics.
During the worldwide economic crisis of the Great Depression in the 1930s, many people lost faith in liberal democracy and countries across the world turned to authoritarian regimes. In Germany, resentment over the terms of the Treaty of Versailles was intensified by the instability of the German political system, as people felt that left- and right-wing parties were struggling for personal power, with no concern for meaningful governance. The most successful political aspirant to emerge from the situation was Adolf Hitler, the leader of the Nazi Party. The Nazis took totalitarian power in Germany from 1933 and demanded the undoing of the Versailles provisions. Their ambitious and aggressive domestic and foreign policies reflected their ideologies of antisemitism, unification of all Germans, the acquisition of "living space" for agrarian settlers, the elimination of Bolshevism and the hegemony of an "Aryan"/"Nordic" master race over "subhumans" such as Jews and Slavs. Other factors leading to the war included the aggression by Fascist Italy against Ethiopia, militarism in Imperial Japan against China, and Nationalists fighting against Republicans for control of Spain.
At first, the aggressive moves met with only feeble and ineffectual policies of appeasement from the other major world powers. The League of Nations proved helpless, especially regarding China and Ethiopia. A decisive proximate event was the 1938 Munich Conference, which formally approved Germany's annexation of the Sudetenland from Czechoslovakia. Hitler promised it was his last territorial claim, nevertheless in early 1939, he became even more aggressive, and European governments finally realized that appeasement would not guarantee peace but by then it was too late.
Britain and France rejected diplomatic efforts to form a military alliance with the Soviet Union, and Hitler instead offered Stalin a better deal in the Molotov–Ribbentrop Pact of August 1939. An alliance formed by Germany, Italy, and Japan from the Tripartite Pact signed in 1940 led to the establishment of the Axis powers.
Ultimate causes
Legacies of World War I
By the end of World War I in late 1918, the world's social and geopolitical circumstances had fundamentally and irrevocably changed. The Allies had been victorious, but many of Europe's economies and infrastructures had been devastated, including those of the victors. France, along with the other victors, was in a desperate situation regarding its economy, security and morale and understood that its position in 1918 was "artificial and transitory". Thus, French Prime Minister Georges Clemenceau worked to gain French security via the Treaty of Versailles, and French security demands, such as reparations, coal payments, and a demilitarised Rhineland, took precedence at the Paris Peace Conference of 1919–1920, which designed the treaty. The war "must be someone's fault – and that's a very natural human reaction", analysed the historian Margaret MacMillan. Germany was made to accept liability for the harm done to the Allies during World War I, and the War Guilt Clause was the basis for reparations to be paid to the Allies, especially France, by Germany. Roy H. Ginsberg argued, "France was greatly weakened and, in its weakness and fear of a resurgent Germany, sought to isolate and punish Germany... French revenge would come back to haunt France during the Nazi invasion and occupation twenty years later".The two main provisions of the French security agenda were war reparations from Germany, to be paid in gold and coal and a detached German Rhineland. The German government printed excess currency, which created inflation, and it borrowed money from the United States. Reparations from Germany were needed to stabilize the French economy. France also demanded for Germany to give France its coal supply from the Ruhr to compensate for the destruction of French coal mines during the war. France also insisted on the demilitarisation of the German Rhineland in the hope of hindering any possibility of a future German attack and giving France a physical security barrier between itself and Germany. The payment of reparations, and the principle of a demilitarized Rhineland, were largely viewed by the Germans as insulting and unreasonable.
The resulting Treaty of Versailles brought a formal end to the war but was judged by governments on all sides of the conflict. It was criticized as neither lenient enough to appease Germany nor harsh enough to prevent it from becoming a dominant continental power again. The German people largely viewed the treaty as placing the blame, or "war guilt", on Germany and Austria-Hungary and as punishing them for their "responsibility", rather than working out an agreement that would assure long-term peace. The treaty imposed harsh monetary reparations and requirements for demilitarization and territorial dismemberment, caused mass ethnic resettlement and separated millions of ethnic Germans into neighboring countries.
Already, during the First World War, inflation had become a serious problem for Germany. The Weimar Republic then printed trillions of marks, much of which went to pay workers striking against French occupation in the Ruhr or to pay back domestic wartime debt without raising taxes, which caused hyperinflation. Hyperinflation further served to discredit the Weimar government. Adolf Hitler, a leader of the Nazi Party, attempted a coup d'état in 1923 in what became known as the Beer Hall Putsch, and he intended to establish a Greater Germanic Reich. Although he failed, Hitler gained recognition as a national hero by the German population.
During the war, German colonies outside Europe had been annexed by the Allies, and Italy took the southern half of Tyrol after the armistice. The war in the east had ended with the defeat and the collapse of the Russian Empire, and German troops had occupied large parts of Eastern and Central Europe with varying degrees of control and established various client states such as a kingdom of Poland and the United Baltic Duchy. The German Navy spent most of the war in port, only to be turned over to the Allies. It was scuttled by its own officers to avoid it from being surrendered. The lack of an obvious military defeat would become one of the pillars holding together the Dolchstosslegende, which gave the Nazis another propaganda tool.
The demilitarised Rhineland and the additional cutbacks on military also infuriated the Germans. Although France logically wanted the Rhineland to be a neutral zone, France had the power to make their desire happen, which merely exacerbated German resentment of the French. In addition, the Treaty of Versailles dissolved the German general staff, and possession of navy ships, aircraft, poison gas, tanks and heavy artillery was also made illegal. The humiliation of being bossed around by the victor countries, especially France, and being stripped of their prized military made the Germans resent the Weimar Republic and idolise anyone who stood up to it. Austria also found the treaty unjust, which encouraged Hitler's popularity.
US President Woodrow Wilson said his Fourteen Points would be a guideline for peace and would not penalize Germany. However Wilson could not convince the Allies to agree to adopt his Fourteen Points and the peace was deliberately harsh on the losers. Germans felt betrayed. The Italians were on the winning side but they too felt betrayed by the Allies who, despite promising them the Italian-inhabited lands of Fiume and Dalmatia in the Treaty of London, ended up giving those lands to the newly-created Yugoslavia instead. The Japanese also started to express resentment for how they were neglected during the negotiations of the Treaty of Versailles. The Japanese proposition to discuss the issue of racial equality was not put in the final draft because of many other Allies, and the Japanese participation in the war caused little reward for the country. The war's economic and psychological legacies persisted well into the Interwar period.
Failure of the League of Nations
The League of Nations was an international peacekeeping organization founded in 1919 with the explicit goal of preventing future wars. The League's methods included disarmament, collective security, the settlement of disputes between countries by negotiations and diplomacy and the improvement of global welfare. The diplomatic philosophy behind the League represented a fundamental shift in thought from the preceding century. The old philosophy of "concert of nations", which grew out of the Congress of Vienna, saw Europe as a shifting map of alliances among nation-states, which created a balance of power that was maintained by strong armies and secret agreements. Under the new philosophy, the League would act as a government of governments, with the role of settling disputes between individual nations in an open and legalist forum. Despite Wilson's advocacy, the United States never joined the League of Nations.The League lacked an armed force of its own and so depended on member nations to enforce its resolutions, uphold economic sanctions that the League ordered. However, individual governments were very reluctant to do so. No military forces were involved in the 1920s when several notable small successes and some early failures happened. In the 1930s, there was only one use of military force, the peaceful 1935 Saar status referendum. The League proved incapable of preventing aggression by Italy against Ethiopia. The reliance upon unanimous decisions, the lack of an independent body of armed forces and the continued self-interest of its leading members meant that historians agree that failure was inevitable.