How can we begin to explain the causes of the First World War?

The best way to tackle the question is first to understand what they are asking of you, and then look closely at how the question is structured because this is often a key to structuring your essay. In this quesiton, there aren't really any clues as to how you can structure the essay so think about what you have learned about the Frist World War. Like any major event in history, there isn't a single cause that led to the outbreak of war. When discussing the causes of the First World War, historians often distinguish between the short and long-term causes that shaped the geopolitics of the region and let to the ultimate outbreak of war. Although the ultimate "spark" that led to the outbreak of the war was the assassination of Franz Ferdinand (the Archduke of Austria-Hungary) in August of 1914, we need to understand why this single even had such an enormous impact in the rest of Europe. Here, you need to consider the four long-term causes, often referred to as "MAIN" (this is a way you can remember them)! First of all, Militarism. At this time, there were 1-3 years of compulsory military in European countries, called standing armies.  This also led to the creation of various Alliance systems - the Triple Alliance (formed of Germany, Austria-Hungary, and Italy) and the Triple Entente (formed with France, Russia, and Britain). Consider also the reasons that led to the formations of these alliances. This will bring us to the third long-term cause, Imperialism, as hegemonies like Germany and Britain begin competing for naval dominance and colonies in Africa. The British were afraid that the Germans were becoming big competitors for markets and colonies in Africa, and the French wanted revenge for a loss they suffered to the Germans in Alsace-Lorraine, 1870. This is why these intricate and interlocking alliances came about. Finally, Nationalism which ties to the aforementioned causes. Britain wanted to protect its naval pride so they abandoned their isolationist policy and signed the Entente Cordiale with France. On the other side, countries like Germany were trying to expand their hegemony and felt threatened by the strong naval power of Britain and the strong French presence in Africa.