This books maps out the territory of international law and religion challenging received traditions in fundamental aspects. On the one hand, the connection of international law and religion has been little explored. On the other, most of current research on international legal thought presents international law as the very victory of secularization. By questioning that narrative of secularization this book approaches these traditions from a new perspective. From the Middle Ages’ early conceptualizations of rights and law to contemporary political theory, the chapters bring to life debates concerning the interaction of the meaning of the legal and the sacred. The contributors approach their chapters from an array of different backgrounds and perspectives but with the common objective of investigating the mutually shaping relationship of religion and law. The collaborative endeavour that this volume offers makes available substantial knowledge on the question of international law and religion.