In August 1914 Germany invaded Belgium. This was a mistake for two reasons. Firstly, Germany broke the treaty of London right from the beginning of the war, lost the support of neutral opinion and justified the Allied entry into the war in defence of Belgium. Secondly, it was very possible that Britain might have entered the war against Germany even if Germany had not invaded Belgium. However, the invasion of Belgium created a situation in which Britain had no option but enter the war; in response to the violation of the treaty of London, to defend the channel ports now threatened by Germany, and to restore the balance of power in Europe. Germany’s action therefore ensured that she had to fight Britain as well as France and Russia. This was quite an important cause for Germany’s failure in world war one as Germany ended up giving aid and support to her allies instead of fighting beside them. This is a large contrast compared to Britain’s allies who were very strong and did not rely on aid from her.
Another reason for Germany’s defeat in the First World War was the entry of the USA into the war in April 1917. The arrival of American troops on the western front by 1918 was not only of great practical assistance to the Allies but also a tremendous boost to their morale. For the Germans, however, it was a huge psychological blow. This was because Russia had just been forced out of the war only to be replaced by one of the strongest countries in the world. American troops and supplies also played an important role in the final offensive on the western front in 1918. The entry of the USA into the First World War meant that Germany’s morale was weakened as they had just managed to defeat another large, strong enemy, Russia, only to be replaced by another.
A new fighter aircraft was introduced, the Sopwith Camel, which proved to be the most successful fighter aircraft of WWI, and gave the allies control of the skies over the western front by 1918. This meant that the allies final land offensive could go ahead without interference from German air attacks. This was not a more important cause for Germany’s defeat than the schlieffen plan but it played a part in weakening Germany which eventually lead to their defeat
British control of the seas and the failure of the German U-boat campaign of unrestricted warfare in 1917 was a vital factor in the Allied victory in 1918.
British control of the seas allowed the Allies to blockade Germany and Austria-Hungary and this led to great shortages of food and raw materials in these countries. The Allies had also seized Germany's colonies and destroyed her roving cruiser squadron. By November 1918 there were food riots and strikes in German cities. This also led to an outbreak of mutiny within the German navy which eventually led to the abdication of the Kaiser and ultimately the German surrender. The U-boat campaign was a major reason for American entry into the war due to the sinking of the Lusitania. The sinking of the Lusitania was a trigger cause for the USA’s entry into the First World War, which was one of the most important causes for Germany’s defeat in World War One.
All three Triple Entente powers made positive contributions to the allied victory. The wealth and industrial power of Britain and her Empire helped the Allies withstand vast expense of war. (In 1918 alone Britain spent £2,700 million.) The French proved to be a determined ally who were prepared to make great sacrifices rather than surrender as seen, for example at Verdun. Until the Revolution of November 1917 took her out of the war, Russia, with her great reserves of manpower, took much strain off the Allies on the Western Front. This was in spite of her own heavy losses on the Eastern Front. The Allied superiority in manpower was vital in a war of ‘attrition’ where casualty rates were so high. This eventually allowed the Allies to overcome the more efficient but smaller German armies. By contrast Germany’s allies – Austria-Hungary, Turkey and Bulgaria – all proved to be weak and in need of support from Germany. Germany's war effort therefore relied mainly on her own strength and, although this was considerable, the odds against her by the end of the war were overwhelming – she was at ware with a total of 27 countries by 1918. This meant that Germany was extremely weak during World War One, spending precious money and supplies to support her allies instead of being spent on the war.
In conclusion, I believe that the most important factor for Germany’s failure in World War I was not the Schlieffen plan but rather the combined power of the Allied forces. This was due to various reasons. Firstly, the wealth of Britain helped the allies withstand the vast expense of war. Britain also had many power allies, such as Russia, which left in 1917, and France, who were determined and had vast amounts of troops. The large numbers of Allied troops were also vital in a war of attrition as casualty rates were very high. In contrast Germany’s allies- Austria-Hungary, Turkey and Bulgaria were very weak and needed aid from Germany, which meant that Germany was on her own. This made it impossible for German to win the war, as she was at war with a total of 27 countries by 1918.