This is a hotly disputed question. At the time, the Germans tended to blame the selfish ambitions particularly of Britain and Russia, while the Allies tended to blame German militarism and aggressive expansionism.
Other historians blame a collective failure of will by all countries to maintain the peace: either all are equally to blame or else they all blindly ‘sleepwalked’ into war without realising what they were doing.
More cynical commentators see the war as the result of colonialist rivalry – a war of expansion on both sides in which the western allies, despite denouncing German expansion, expanded their own empires significantly.
Others again see the First World War as the result of capitalist expansion, in which the ostensible causes were mere excuses for profiteering at the expense of the lives of the working people of all the combatant countries.
Seán Lang is a senior lecturer in history at Anglia Ruskin University, and the author of First World War for Dummies.
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