THE HOLY ROMAN Empire, Voltaire famously (and inaccurately) remarked, 'was neither holy, nor Roman, nor an empire'. As a put-down, it could hardly have been more successful. For while most schoolboys can tell you about the Third Reich, and a select few can even identify the Second (of 1871-1918), almost none have the slightest idea about the First - ironically, the only one of the three that I really did 'last for a thousand years', until its dissolution at the hands of Napoleon in 1806. If there is a single reason why we English, habituated for centuries to the constitutional simplicities of our nation-state, fail to understand Continental thinking on the 'European project', it is our almost total ignorance of this complicated, but extraordinarily successful, institution: a maze of 111 and partial sovereignties that provided a unified juridical framework for much of Europe - from Brussels to Berlin, the Adriatic to the Baltic - throughout most of the pre-Napoleonic millennium.

For a glimpse of its complexity, and of its centrality to European life. there is hardly a better face to start than Philip Mansel's  fine new biography of one of its most colourful and rakish grandees: Charles-Joseph, seventh Prince de Ligne. Raconteur, wit, seducer, and would-be counsellor of kings, Ligne conquered