At the end of June 1914, the young Oxford historian E. L. Woodward was spending part of his summer vacation at a resort in the Black Forest. In the late afternoon of Sunday, 28 June, the polite tinkling of cosmopolitan teacups on the long terrace of the Badenweiler spa hotel was interrupted by some startling news: the Archduke Franz Ferdinand, heir to the Habsburg throne and future ruler of some forty-five million people in central and south-eastern Europe, had been assassinated in Sarajevo. The hotel crowd excitedly dispersed to form separate groups according to nationality: ‘I knew that something very grave had happened’, Woodward reflected many decades later. Something grave had indeed happened, though Woodward was perhaps reading back into the past a fancy of foresight.

When viewed at the distance of a century, there is a paradox about 1914: it should have been an unremarkable year. After years of turmoil, especially in south-eastern Europe, the short-term indicators pointed towards peace. European diplomats spoke of a new era of détente. But the two recent Balkan conflicts in 1912 and 1913 had left unexploded ordnance in their wake, one being Albania, now independent but without agreed frontiers. Under the rule of a German princeling, the Prince of Wied, the country was on the verge of becoming a failed state: ‘les caisses sont vides, le thrône est Wied, tout est vide [the coffers are empty, [on] the throne is Wied, everything is empty]’, as some unkindly soul put it in the spring of 1914. But whilst there were problems in the periphery of Europe, relations between the Great Powers appeared relatively free of friction, especially when compared with previous years. To explain how and why the Powers found themselves in a world war, then, poses a significant challenge to the student of the past.