In the past, international law only applied to sovereign states and the Holy See. In recent years, international organizations have been recognized as relevant parties. Today, corporations and individuals are also included in some categories of international law. Here is a history of some of the most important norms and the history of their development. This article aims to shed light on the foundations and development of international law. Let us explore the most important norms, and how they are used in contemporary society.

The rule of law is a way to resolve conflicts between states. The rules of international law govern the relations between states. They are the products of the free will of states, and are expressed in conventions, usages, and agreements. These documents govern the relations of independent communities and help them achieve their common goals. They are not presupposed to restrict the independence of states. They are governed by the intent of the creators, and are derived from the free will of those countries.

One of the oldest sources of international law is international agreements. The earliest known treaty was made in 1380 B.C. between the Hittite king Suppiluliuma I and the Aziras of Amurru, a part of the Egyptian empire. From these agreements came customary law. This is a category of peremptory norms in international law. It is reflected in the Vienna Convention on the Law of Treaties, which states that nations cannot contract out of their prohibition on slavery.