This book has been written as a sustained engagement with the enigma of sovereignty. In it I have explored a particular aspect of sovereignty, namely juridical sovereignty, in a particular context, namely that of the international legal order. At the same time, I have offered an episodic account of institutional or regime innovation in the two centuries since 1815. I have argued that juridical sovereignty can be best understood as an interplay between conventional international legal conceptions of sovereign equality and two, often obscured, categories of sovereignty inhabited by the Great Powers and outlaw states. I use the term ‘legalised hegemony’ to capture the special position of the Great Powers in international society since 1815 and I focus on the institutional prerogatives they have enjoyed in this period and the manner in which this hegemony is accommodated within the system of ‘sovereign equals’. Meanwhile, ‘anti-pluralism’ (and, in particular, its ascendant form, liberal anti-pluralism) is a way of organising inter-state relations according to hierarchies based on the internal politics, moral characteristics or temperament of nation-states. Anti-pluralism, then, suspends the conventional rights and immunities of certain sovereign states and characterises them as outlaw states or uncivilised nations. The combination of legalised hegemony and anti-pluralism produces a society in which, to some degree, all states are ‘unequal sovereigns’.

James Lorimer once said of Grotius that, ‘after having laid down his principles he left them there without making any use of them …’.