Most and Least Important Factors in the Outbreak of Ww1

Which was the most important and least important factor in the outbreak of the First World War? In my opinion, the most important cause of the First World War was the Alliance System. By 1914, the main powers in Europe had been divided into two groups.
These were: The Triple Alliance – Germany, Austria-Hungary and Italy, and The Triple Entente – Britain, France and Russia. Although the point of creating these alliances was to avoid war, they meant that any conflict that broke out would increase in scale immediately because the other countries had to support them. The main rivalries were Germany and France over the capture of Alsace-Lorraine, Russia and Austria over the Balkans, and Britain and Germany over their navies and economic power.
The Alliance System created a lot of competition between the rival countries, and possibly even the allies themselves, because, naturally, they all wanted to be the most powerful and influential in their group. This just increased the tension between everyone and strengthened each side for the inevitable war. On the other hand, I think the least important cause of the war was the Arms Race. The growing divide in Europe (caused by the Alliance System) had led to an arms race between the main countries.

The French and German armies had more than doubled their forces, and all nations were making plans for war. The German Count Alfred von Schlieffen had come up with the Schlieffen Plan, which was to fight France and defeat them within six weeks, and then to turn back and defeat Russia. Unfortunately for them, they relied too much on hoping Russia would take more than six weeks to mobilise, which didn’t happen. Also, as the Germans went through Belgium to get into France, Belgium had a treaty with Britain which meant Britain automatically got involved.
Austria was intimidated by Russia and needed Germany to succeed in defeating France, so they could then help them in fighting Russia. Russia had potentially millions of soldiers. This made them very powerful because they could overwhelm the opposition with sheer numbers, although they would have needed Britain’s industrial help because they were badly-equipped. France had a large, well equipped army. They had a plan called Plan 17. This was to charge across the frontiers and deep into Germany, forcing them to surrender.
Britain was closely but secretly in collaboration with the French. They set up the BEF (British Expeditionary Force), which was 150,000 highly trained soldiers that could go and support France at any time. Although the Arms Race seems to have developed the preparations for war from each country, I don’t think that it actually caused any more problems between the countries. At this point, war was seen as inevitable and all the nations could do was prepare for what was to come as best as they could.