At first sight, John Locke would be an even less likely candidate than Thomas Hobbes for inclusion in the canon of the history of international thought. None of his major published writings, among them the three Letters on toleration (1689, 1690, 1692), the Essay Concerning Human Understanding (1689/90), the Two Treatises of Government (1689/90), Some Thoughts Concerning Education (1693) and The Reasonableness of Christianity (1695), was primarily or even substantially concerned with any of the subjects that would now be considered under the rubrics of International Relations or international law. Most of Locke’s attempts in these works to theorise the relations between peoples and states, to derive norms for international relations or to describe and analyse the international society of his times, were relatively brief and episodic. And the various reflections on England’s foreign affairs scattered throughout his correspondence and manuscripts were not widely circulated in his lifetime and remain little known even today. In short, the question of Locke’s international thought seems to be like the puzzle of the dog that did not bark in the night.