Final answer:
The First World War had complex causes including militarism, alliances, imperialism, nationalism, and the assassination of Archduke Franz Ferdinand.
Step-by-step explanation:
The First World War, also known as the Great War, was a complex event with various causes. Some of the key factors that contributed to the outbreak of the war include militarism, alliances, imperialism, nationalism, and the assassination of Archduke Franz Ferdinand of Austria-Hungary. Militarism played a significant role as nations engaged in an arms race and built-up their military forces, raising tensions between countries. Alliances formed between countries created a web of obligations and increased the likelihood of conflict being triggered. Imperialism and the competition for colonies also heightened tensions, as nations sought to expand their influence and control. Nationalism, which promoted loyalty and devotion to one's country, fueled rivalries and created a strong sense of patriotism that led to aggressive actions. Lastly, the assassination of Archduke Franz Ferdinand in 1914 by a Serbian nationalist was the spark that ignited the war as it triggered a series of events that led to the mobilization of armies and the declaration of war.
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