‘Everything has changed in our civilisation; it has made much fortunate progress, but it has also left us some new vices’, wrote Joseph Fouché, Napoleon’s former police chief, with some pessimism, after the Battle of Waterloo in 1815. It was ‘no longer possible to govern men in the same manner’, he feared, and he was not the only one to have such concerns. Across Europe, a whole generation of the political and social elite was permanently scarred by the events of the French Revolution and its aftermath. Long after the defeat of Napoleon, these elites remained terrified by the prospect of disorder, radicalism and anarchy. In this elegant and panoramic survey of Britain, France, Germany, Austria and Russia, Adam Zamoyski explores this state of terror using a wide selection of manuscript sources, state papers, diplomatic correspondence and diaries. These abound ‘in imagery of volcanic eruption engulfing the entire social and political order’ and express ‘an almost pathological dread that dark forces were at work undermining the moral fabric on which that order rested’.