answer: Some of the most important long term or structural causes are: the growth of nationalism across Europe, unresolved territorial disputes, an intricate system of alliances, the perceived breakdown of the balance of power in Europe, convoluted and fragmented governance, the arms races of the previous decades, previous military planning, imperial and colonial rivalry for wealth, power and prestige, and economic and military rivalry in industry and trade – e.g., the Pig War between Austria and Serbia.