Charles de Gaulle famously called the Second Vatican Council the most important event in modern history. Many commentators at the time saw the Council as nothing short of revolutionary, and the later judgements of historians have upheld this view. The astonishing enterprise of a man who became, quite unexpectedly, Pope John XXIII in 1958, this purposeful aggiornamento of the Roman Catholic Church was almost at once a leviathan of papers, committees, commissions, and meetings. Scholars have been left to confront no less than twelve volumes of ‘ante-preparatory’ papers, seven volumes of preparatory papers, and thirty-two volumes of documents generated by the Council itself. A lasting impression of the impressiveness of the affair is often conveyed by photographs of the 2,200-odd bishops of the Church, drawn from around the world, sitting in the basilica of St Peter, a vast, orchestrated theatre of ecclesiastical intent. For this was the council to bring the Church into a new relationship with the modern world, one that was more creative and less defiant; a council to reconsider much – if not quite all – of the theological, liturgical, and ethical infrastructure in which Catholicism lived and breathed and had its being.