Causes of the Second World War

The Causes of the Second World War

The outbreak of war in Europe in September, 1939, was the result of a number of factors. In simple terms the aggressive foreign policy of Hitler’s Third Reich and the lack of preventative measures by the major european powers to prevent Hitler’s increasing use of force in the mid to late 1930’s is to blame for the onset of Europe wide conflict. However this is a rather simplistic view of the reasons. War broke out in 1939 for a variety of reasons which can be traced back to the First World War and the peace treaties that were imposed on the defeated nations in its aftermath.


Following the armistice of 1918 the the victorious Allied forces created a peace settlement that was designed to prevent the reemergence of a warring German race. In doing so they isolated Germany, restricted opportunities for German integration into the politics of Western Europe and sowed the seeds of German discontent. The high levels of unemployment in Germany following the war, and the growing feeling that the troops had been ‘stabbed in the back’ provided extremist political groups an ideal opportunity to win support. With Allied troops occupying parts of Germany and huge swathes of land being removed from the control of the Weimar Government, it was easy for political groups to point to the terms of the Treaty of Versailles and suggest that things would be much better if they were revoked.

The Great Depression and the Rise of the Nazi Party

The fall of the Wall Street Stock Exchange in 1929 led to the onset of a second era of great economic depression. This corresponded with the rise of extremist groups in Germany. In 1933 the National Socialist German Workers Party (NSDAP) managed to take control of the Reichstag, the German parliament. Hitler had stated that one of his aims was to free Germany from the shackles of the Treaty of Versailles. This was done in a number of ways: first, the Rhineland was reoccupied. There was relatively little opposition to this breach of the Terms of the Treaty of Versailles. French politicians made representations about it, but nothing was done to prevent the actions taking place. Indeed, many politicians felt that this was an entirely reasonable thing for Germany to do and few felt that this move was a sign of more sinister things to come.

Failures of the League of Nations

Hitler’s following breaches of the terms of Versailles made it increasingly apparent that conflict may occur in Europe. Hitler deployed troops in the Spanish Civil War, supporting the fascist forces of Franco. He also formed a close alliance with the fascist dictator of Italy, Benito Mussolini. Now there was an axis of Power in the centre of Europe. Now there were two right wing dictators with expansionist aims. The manner in which these aims were addressed by the rest of Europe is open to debate. The League of Nations was supposed to mediate in cases of territorial dispute and to act as arbitrator between two nations struggling to maintain reasonable diplomatic relations. The dictators of Europe were encouraged by the inability of the League to prevent them taking action, however. They looked to the Japanese invasion of Manchuria in 1933 and noted the League’s failure to prevent Japanese expansion. In 1936 Mussolini ordered Italian troops to invade Abyssinia (Ethiopia). The League of Nations took 2 months to decide upon a response, which then lacked ‘teeth’.


These decisions gave the dictators confidence that they would be able to press their claims for territory without facing real opposition from France, Britain and the United States. Consequently the German Fuhrer, Adolf Hitler took opportunities to remove further terms of the Treaty of Versailles. German armed forces were strengthened and loop holes in the clauses of the treaty of Versailles were exposed and exploited. Diplomatic efforts were heightened to further German claims for territory in the East, aiming to enable Lebensraum. In 1938 German troops annexed Austria, creating Anschluss, or a united Greater Germany. Unopposed Hitler then looked to the Sudentenland. This was an area of Czechoslovakia that was populated by predominantly ethic Germans. Hitler demanded a plebiscite to decide the governance of the land.


The Sudetenland crisis made the approach of Britain and France more open and obvious. Both nations pursued a policy of appeasement. In this policy Hitler was granted some of his wishes as they were considered to be reasonable, whilst diplomatic pressure was used to prevent him from going too far. Historians have debated whether this policy was sensible or not. Churchill, most famously, opposed the policy from the start and argued that decisive action had to be taken to prevent the onset of European conflict. Others at the time, believed that appeasement may allow Germany to restore her national self esteem and be gradually welcomed back into the political community. A third view was that appeasement could be used to buy time to rearm the allied forces in preparation for a conflict that was increasingly likely: military expenditure rose in Britain at the same time as the policy of Appeasement was being pursued.

Whatever the aim of Appeasement, Hitler viewed it as a weakness. Britain and France were extremely unlikely, in his mind, to do anything to prevent his expansion into the East, certainly not in the short term. The Sudentenland was ceded to Germany as a result of the plebiscite. Hitler then invaded the remainder of Czechoslovakia. The response of the British and French was to seek assurances from Hitler that he had no further demands. At the Munich Conference such assurances were made, and Hitler informed that any further actions of this nature would lead to war, a reference to Hitler’s ambitions in Poland.


Following the Munich Agreement there was a flurry of diplomatic meetings with representatives of the Soviet Union. The British and French sought an alliance with the USSR as they believed that Hitler would be reluctant to invade Poland without the support of Stalin. Similarly, Hitler sought support from the USSR as he did not want to engage in war with Russia at this time. In August 1939, the German and Soviet foreign ministers made an agreement that gave half of Poland to each nation, in the event of a war. Confident that the Western European nations would not intervene in an Eastern European conflict, Hitler’s troops were ordered to invade Poland on the First of September 1939. The British and French declared war on Germany as a result.

Summary: Causes of the Second World War

The severity of the Treaty of Versailles
The failure of the league of Nations to intervene
The policy of Appeasement led Hitler to believe that the Allies would not use force
Hitler’s personality and demands.
Agreements with the USSR

Second World War
Causes of the Second World WarHow well prepared for war was Germany in 1939?How well prepared for war was Poland in 1939?
How well prepared for war was Britain in 1939?How well prepared was the Soviet Union for war in 1939?How well prepared for war was France in 1939?
Statistical analysis of Europe's readiness for war in 1939
Documents and Personal Histories of the Second World War
Battle of the Bulge. Diary EntriesAircraft Recognition SketchesAir Raid Roles and Precautions
Dealing with wartime bereavement

Second World War

Causes of the Second World War How well prepared for war was Germany in 1939? How well prepared for war was Poland in 1939?
How well prepared for war was Britain in 1939? How well prepared was the Soviet Union for war in 1939? How well prepared for war was France in 1939?
Statistical analysis of Europe’s readiness for war in 1939

Documents and Personal Histories of the Second World War

Battle of the Bulge. Diary Entries Aircraft Recognition Sketches Air Raid Roles and Precautions
Dealing with wartime bereavement

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