The cause for WWI was the assassination of Archduke Franz Ferdinand at Sarajevo on 28 June 1914. However historians feel that a number of factors contributed to the rivalry between the great powers that allowed war on such a wide-scale to break out.

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Consensus on the origins of the war remains elusive since historians disagree on key factors and place differing emphasis on a variety of factor the deepest distinction among historians is between those who focus on the actions of Germany.