Introduction

Traditionally, public international law has long been thought of as largely a law of co-existence: rules of international law were created, either by custom or by bilateral treaty, for the purpose of delimiting spheres of influence between states, but not much else. For the better part, international law regulated the practical aspects of sovereign states living together on Planet Earth, dealing with such issues as the jurisdiction of states, access to each other's courts, delimitation of maritime zones, and other similar issues.

To the extent that cooperation took place at all, it was of the sort which follows naturally from this co-existential character of the law. Thus, if the spheres of jurisdiction of states have been strictly delimited, it follows that rules and procedures are required, for example, to make possible the extradition of criminals captured abroad, or the enforcement of contracts concluded with foreign partners.

Although embryonic forms of international organization have been present throughout recorded history, for instance in the form of the so-called amphictyonic councils of ancient Greece, the late-medieval Hanseatic League or such precursors as the Swiss Confederation and the United Provinces of the Netherlands, it was not until the nineteenth century that international organizations as we know them today were first established. Moreover, it was not until the nineteenth century that the international system of states (at least within Europe) had become sufficiently stable to allow those states to seek forms of cooperation.