In Robert Musil’s The Man Without Qualities, a book that encapsulates like no other the ineffable muddle of the Habsburg Empire, the eminent statesman Count Leinsdorf struggles to define the essence or even the raison d’être of the empire. His antithesis, the Prussian Jewish financier Arnheim, cherishes his visits to what he calls ‘the fairyland’ of Vienna, in which he can relax and take ‘a rest from reason’.

Historians, too, have often tended to take a rest from reason and look for sentimental explanations as they grapple with the problem of how a monarchy ruling over an inchoate geographical area with a dizzying variety of ethnic groups speaking scores of languages and practising half a dozen religions could have worked at all. Not so Pieter Judson, whose crisply written and nuanced study focuses on the tangible elements that created and held the monarchy together for a century and a half before tearing it apart in 1918. With invigorating precision, he analyses how the state was built up by various forces working simultaneously from above and below. His view is not blurred by the unhelpful nostalgia with which so many accounts are suffused. He stresses that although these forces appeared to be engaged in the same project, they were on the whole driven by healthy self-interest. Yet, as he points out, they succeeded in creating a model of imperial citizenship that promised equal opportunities to, and imposed common standards on, peoples who are today citizens of twelve different countries.

In 1770 the empress Maria Theresa ordered that every house, cottage and hovel throughout her dominions be given a number. The operation, which was carried out by the army, was the first link in a chain that was to bind monarch and subjects in a tight embrace that became the