Literature Notes – Week 1
Gleider Hernandez, International Law – Chapter 1, The History and Nature of International
Law
1.1 Introduction: International Law as law
International law is different to national law in that it does not regulate the behaviour of
individuals but rather governs the relations between states. Public international law then
regulates the relations between states and private international law regulates the conflicts
between rules of different domestic legal orders, which might involve individuals with a foreign
or transboundary element. The purposes of International Law have shifted over time and the
underlying ideas and assumptions have also changed.
1.2 The origins of modern international law
1.2.1 The Peace of Westphalia (1648)
Under the Peace of Westphalia, each state would be free to choose its own religion and they
were now considered as equal and sovereign in their relations with one another without
external interference.
1.2.2 The rise and decline of natural law (1648-1815)
Dutch International lawyer Hugo de Groot portrayed International Law as a combination of
two distinct bodies, jus naturale and just gentium. The former described the laws that
“existed within nature”; they were universal and eternal and could be discovered by human
reasoning. The latter, meaning the law of nations, was a human invention, was subject to
change and was based on the consent of states. Later, Emmerich De Vattel, delineated
between “laws of conscience” (natural law) and “laws of action” (positive law) and asserted
that only the latter were relevant.
1.2.3 The nineteenth century and the rise of positivism
1.2.3.1 The dominance of positivism
Within International Law, Enlightenment ideas lead to the abandonment of the idea of the
“law of nature”, rooted in Christian universalism, and the emergence of positivism as a
dominant way of thinking about international law. Positivism was first coined by Auguste
Comte to describe the move away from theological and metaphysical ways of thinking,
looking instead at what has been made by human beings. Within domestic legal orders, law
became dependent on the will of the sovereign and it followed that the sovereign state
became central to international law.
1.2.3.2 Further developments in the nineteenth century
The positivist spirit was to foster unprecedented cooperation between states and fostered
the first international organisations.
1.3 Colonialism and empire
The role of international law in imperialism was twofold. On the one hand, international law
could be a tool to resist European claims to expansion. On the other hand, however,
international law was complicit in providing the legal vocabulary and concepts which facilitated
the conquest of non-European lands by European powers, such as the terra nullius principle or
the scramble for Africa.
1.4 The Twentieth Century
1.4.1 World War I and the League of Nations
Several developments mark the end of World War I, the most important of which was the
signing of the Covenant of the League of Nations. Since its Council was dominated by its
permanent members it was redolent of the Concert of Europe and further embedded the
, idea that powerful states had a special guardianship over the international order. Another
important development was the Kellog-Briand Pact which played a crucial role in laying down
a prohibition on aggressive war which would later be embodied in the UN Charter.
1.4.2 The United Nations during the Cold War (1945-1989)
In response to World War II the Charter of the United Nations was signed in order to
preserve international peace and security. The UN Charter’s striking feature is the ambitious
prohibition in Article 2(4) on recourse to war and the use of force in inter-state relations. A
second pillar is the promotion of international cooperation. The third pillar, in relation to
development, reflected how the post-war period saw the gaining of independence of former
colonies across Africa and Asia. After 1945, the sovereign state remained the subject of
academic debate, though international law developed with great strides in cooperation in
new sectors.
1.5 International Law since 1989
1.5.1 The end of the Cold War
After the Cold War, scholarship, though still filtered through the lens of positivism, began to
take on a strongly normative character, guided by liberal ideals of democracy and free
market economics.
1.6 The contemporary international legal system
1.6.1 Sovereign equality of states
A striking feature of states is their “sovereign equality” as recognised in Article 2(1) of the UN
Charter and is a formal confirmation that states enjoy equal footing as international legal
subjects. The theory of sovereignty, by Bodin, has moreover both outward-facing and
inward-facing dimensions, referring to both the freedom of a state from the command of any
other state, and its “original” exclusive power to wield legal authority over its subjects.
1.6.2 Decentralised authority
The decentralised nature of international law is its second characteristic feature, as it
recognises multiple and equal sovereign entities, states and purports to regulate relations
between them. This therefore remains a horizontal legal order.
1.6.3 The basis of obligation of international law
Today, the UN Charter and several important multilateral instruments limit states’ freedom
of action in relation to using force against one another and enjoin them to respect certain
fundamental human rights. Under the classical view of international law, the binding nature
of such obligations for states seems based on consent; only those obligations to which a
state will have committed herself will be considered binding. The principle of reciprocity is
important here, as it induces states to limit their freedom of action in return for others to do
likewise.
1.6.4 Is international law a “system”?
All of this begs the question of whether international law constitutes a functioning system
under the name of law. For the theory and debates, see theory and debates on p. 24-25.
1.7 Contemporary debates in international law
It is important to briefly address some criticisms of international law. First, its development has
been decidedly Eurocentric, giving rise to new schools of thought from other parts of the world.
Second, from an international relations point of view, international law is often only secondary to
other considerations.
Gleider Hernandez, International Law – Chapter 2, Sources of international law
2.1 Introduction: sources and the nature of international law
