For the reign of law in international relations

“Justitia et pace” - Justice and peace - is the slogan of this nongovernmental organization of lawyers, founded in 1873. The Belgian lawyer Gustave Rolin-Jaequemyns was the initiator, and the aim was to build an international institute which would be an authority on international law. The organization he created is still working to make the rules of international law, not war and violence, the guidelines for relations between sovereign states.

In 1904, the Institute of International Law won special praise for promoting international arbitration and for persuading states to accept the rules of law in wartime. The Institute was among other things given the credit for the provisions on arbitration which were adopted by the Hague Congress in 1899. In the inter-war years, the work of the Institute was very important to the League of Nations. Since 1945 the United Nations has found the reports and legal interpretations issued by the Institute of International Law very helpful.

The seat of the Institute is at the Secretary-General's place of residence.