All but immediately its title became a catchword for politicians warning of the dangers of any repetition of what had brought the war about, and the need to insure against them. The book that met with this response was the work of a historian born well after the Second World War, in a country that had entered the First World War not as a Great Power, or even an independent participant, but as an auxiliary of the most global of its belligerents.
Clark is a descendant, he explains, of a refugee from the Irish famine in colonial Australia. Widespread public acclaim—critical or official—is far from a guarantee of worth. In matters intellectual, frequently the opposite. But not invariably, and this is such a case. By any measure, The Sleepwalkers is a great work of history.
What sets it apart within the literature on the First World War that now stretches back for over a hundred years, and continues to accumulate with little sign of dwindling, are five achievements. First and foremost is the sheer range of its coverage, encompassing in a single volume not only the full Pentarchy of Great Powers which plunged into the war—which was, after all, game too for Fay and Schmitt at the outset of its historiography—together with Serbia, subject to extended scrutiny by Albertini, but drawing on a much wider body of evidence and argument about its onset than ever before.
The condition of that range is a polymathic ease in the languages of Europe beyond the scope of any precursor, yielding a command of sources—primary and secondary—not just in French, German, Italian and Russian, but Serbo-Croatian, Polish and Dutch to boot.
Married to depth of scholarship is pace of narrative. Clark handles the problem with brio, to such effect that the book was from the start a best-seller. At the same time, cross-cutting the story is an analytic of power and rule that, as Clark would have it, set the parameters for the political actors of the period.
