What were the four main causes of world war 1 and which was most significant?

1) militarism- Germany began to build up their military to compete with Britain
2) imperialism- Germany began to collect more and more land which got everyone scared
3) nationalism- Austria-Hungary wanted to expand their land but they could only expand into Russia
4) Alliances- alliances were the main cause of the war due to country’s going to war and allying country’s to join the war.
There was one main event that took place which was the death of two people. The Archduke of Austria-Hungary Franz Ferdinand and his wife Duchess Sophia

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